├── .DS_Store
├── .Rbuildignore
├── .gitignore
├── DESCRIPTION
├── LICENSE
├── NAMESPACE
├── R
├── .DS_Store
├── conRelPlot.r
├── itemDistribution.r
├── itemInfoPlot.r
├── itemfitPlot.r
├── itempersonmap.r
├── personDistribution.r
├── personfitPlot.r
├── scaleCharPlot.r
├── sim_irt.r
├── summaryPlot.r
├── testInfoCompare.r
├── testInfoPlot.r
├── tracePlot.r
└── utils-pipe.r
├── README.md
├── README.rmd
├── ggmirt.Rproj
├── inst
└── figures
│ └── logo.png
└── man
├── conRelPlot.Rd
├── figures
├── README-unnamed-chunk-10-1.png
├── README-unnamed-chunk-2-1.png
├── README-unnamed-chunk-2-2.png
├── README-unnamed-chunk-3-1.png
├── README-unnamed-chunk-4-1.png
├── README-unnamed-chunk-5-1.png
├── README-unnamed-chunk-6-1.png
├── README-unnamed-chunk-7-1.png
├── README-unnamed-chunk-8-1.png
└── README-unnamed-chunk-9-1.png
├── itemDist.Rd
├── itemInfoPlot.Rd
├── itemfitPlot.Rd
├── itempersonMap.Rd
├── personDist.Rd
├── personfitPlot.Rd
├── pipe.Rd
├── scaleCharPlot.Rd
├── sim_irt.Rd
├── summaryPlot.Rd
├── testInfoCompare.Rd
├── testInfoPlot.Rd
└── tracePlot.Rd
/.DS_Store:
--------------------------------------------------------------------------------
https://raw.githubusercontent.com/masurp/ggmirt/4cfa1069f12409e0d8420ec67468a7f32351d0b3/.DS_Store
--------------------------------------------------------------------------------
/.Rbuildignore:
--------------------------------------------------------------------------------
1 | ^.*\.Rproj$
2 | ^\.Rproj\.user$
3 |
--------------------------------------------------------------------------------
/.gitignore:
--------------------------------------------------------------------------------
1 | .Rproj.user
2 | .Rhistory
3 | .RData
4 | .Ruserdata
5 | .DS_Store
6 |
--------------------------------------------------------------------------------
/DESCRIPTION:
--------------------------------------------------------------------------------
1 | Package: ggmirt
2 | Title: Plotting functions to extend "mirt" for IRT analyses
3 | Version: 0.1.0
4 | Authors@R:
5 | person(given = "Philipp K.",
6 | family = "Masur",
7 | role = c("aut", "cre"),
8 | email = "phil.masur@gmail.com",
9 | comment = c(ORCID = "https://orcid.org/0000-0003-3065-7305"))
10 | Description: This package provides convenient plotting functions to extend the great package "mirt" with ggplot-based plotting functions. Additionally, it includes some additional summary functions.
11 | License: GPL-3
12 | Imports:
13 | mirt,
14 | magrittr,
15 | dplyr,
16 | tidyr,
17 | ggplot2
18 | Suggests:
19 | tidyverse
20 | Encoding: UTF-8
21 | LazyData: true
22 | Roxygen: list(markdown = TRUE)
23 | RoxygenNote: 7.2.0
24 |
--------------------------------------------------------------------------------
/LICENSE:
--------------------------------------------------------------------------------
1 | GNU GENERAL PUBLIC LICENSE
2 | Version 3, 29 June 2007
3 |
4 | Copyright (C) 2007 Free Software Foundation, Inc.
5 | Everyone is permitted to copy and distribute verbatim copies
6 | of this license document, but changing it is not allowed.
7 |
8 | Preamble
9 |
10 | The GNU General Public License is a free, copyleft license for
11 | software and other kinds of works.
12 |
13 | The licenses for most software and other practical works are designed
14 | to take away your freedom to share and change the works. By contrast,
15 | the GNU General Public License is intended to guarantee your freedom to
16 | share and change all versions of a program--to make sure it remains free
17 | software for all its users. We, the Free Software Foundation, use the
18 | GNU General Public License for most of our software; it applies also to
19 | any other work released this way by its authors. You can apply it to
20 | your programs, too.
21 |
22 | When we speak of free software, we are referring to freedom, not
23 | price. Our General Public Licenses are designed to make sure that you
24 | have the freedom to distribute copies of free software (and charge for
25 | them if you wish), that you receive source code or can get it if you
26 | want it, that you can change the software or use pieces of it in new
27 | free programs, and that you know you can do these things.
28 |
29 | To protect your rights, we need to prevent others from denying you
30 | these rights or asking you to surrender the rights. Therefore, you have
31 | certain responsibilities if you distribute copies of the software, or if
32 | you modify it: responsibilities to respect the freedom of others.
33 |
34 | For example, if you distribute copies of such a program, whether
35 | gratis or for a fee, you must pass on to the recipients the same
36 | freedoms that you received. You must make sure that they, too, receive
37 | or can get the source code. And you must show them these terms so they
38 | know their rights.
39 |
40 | Developers that use the GNU GPL protect your rights with two steps:
41 | (1) assert copyright on the software, and (2) offer you this License
42 | giving you legal permission to copy, distribute and/or modify it.
43 |
44 | For the developers' and authors' protection, the GPL clearly explains
45 | that there is no warranty for this free software. For both users' and
46 | authors' sake, the GPL requires that modified versions be marked as
47 | changed, so that their problems will not be attributed erroneously to
48 | authors of previous versions.
49 |
50 | Some devices are designed to deny users access to install or run
51 | modified versions of the software inside them, although the manufacturer
52 | can do so. This is fundamentally incompatible with the aim of
53 | protecting users' freedom to change the software. The systematic
54 | pattern of such abuse occurs in the area of products for individuals to
55 | use, which is precisely where it is most unacceptable. Therefore, we
56 | have designed this version of the GPL to prohibit the practice for those
57 | products. If such problems arise substantially in other domains, we
58 | stand ready to extend this provision to those domains in future versions
59 | of the GPL, as needed to protect the freedom of users.
60 |
61 | Finally, every program is threatened constantly by software patents.
62 | States should not allow patents to restrict development and use of
63 | software on general-purpose computers, but in those that do, we wish to
64 | avoid the special danger that patents applied to a free program could
65 | make it effectively proprietary. To prevent this, the GPL assures that
66 | patents cannot be used to render the program non-free.
67 |
68 | The precise terms and conditions for copying, distribution and
69 | modification follow.
70 |
71 | TERMS AND CONDITIONS
72 |
73 | 0. Definitions.
74 |
75 | "This License" refers to version 3 of the GNU General Public License.
76 |
77 | "Copyright" also means copyright-like laws that apply to other kinds of
78 | works, such as semiconductor masks.
79 |
80 | "The Program" refers to any copyrightable work licensed under this
81 | License. Each licensee is addressed as "you". "Licensees" and
82 | "recipients" may be individuals or organizations.
83 |
84 | To "modify" a work means to copy from or adapt all or part of the work
85 | in a fashion requiring copyright permission, other than the making of an
86 | exact copy. The resulting work is called a "modified version" of the
87 | earlier work or a work "based on" the earlier work.
88 |
89 | A "covered work" means either the unmodified Program or a work based
90 | on the Program.
91 |
92 | To "propagate" a work means to do anything with it that, without
93 | permission, would make you directly or secondarily liable for
94 | infringement under applicable copyright law, except executing it on a
95 | computer or modifying a private copy. Propagation includes copying,
96 | distribution (with or without modification), making available to the
97 | public, and in some countries other activities as well.
98 |
99 | To "convey" a work means any kind of propagation that enables other
100 | parties to make or receive copies. Mere interaction with a user through
101 | a computer network, with no transfer of a copy, is not conveying.
102 |
103 | An interactive user interface displays "Appropriate Legal Notices"
104 | to the extent that it includes a convenient and prominently visible
105 | feature that (1) displays an appropriate copyright notice, and (2)
106 | tells the user that there is no warranty for the work (except to the
107 | extent that warranties are provided), that licensees may convey the
108 | work under this License, and how to view a copy of this License. If
109 | the interface presents a list of user commands or options, such as a
110 | menu, a prominent item in the list meets this criterion.
111 |
112 | 1. Source Code.
113 |
114 | The "source code" for a work means the preferred form of the work
115 | for making modifications to it. "Object code" means any non-source
116 | form of a work.
117 |
118 | A "Standard Interface" means an interface that either is an official
119 | standard defined by a recognized standards body, or, in the case of
120 | interfaces specified for a particular programming language, one that
121 | is widely used among developers working in that language.
122 |
123 | The "System Libraries" of an executable work include anything, other
124 | than the work as a whole, that (a) is included in the normal form of
125 | packaging a Major Component, but which is not part of that Major
126 | Component, and (b) serves only to enable use of the work with that
127 | Major Component, or to implement a Standard Interface for which an
128 | implementation is available to the public in source code form. A
129 | "Major Component", in this context, means a major essential component
130 | (kernel, window system, and so on) of the specific operating system
131 | (if any) on which the executable work runs, or a compiler used to
132 | produce the work, or an object code interpreter used to run it.
133 |
134 | The "Corresponding Source" for a work in object code form means all
135 | the source code needed to generate, install, and (for an executable
136 | work) run the object code and to modify the work, including scripts to
137 | control those activities. However, it does not include the work's
138 | System Libraries, or general-purpose tools or generally available free
139 | programs which are used unmodified in performing those activities but
140 | which are not part of the work. For example, Corresponding Source
141 | includes interface definition files associated with source files for
142 | the work, and the source code for shared libraries and dynamically
143 | linked subprograms that the work is specifically designed to require,
144 | such as by intimate data communication or control flow between those
145 | subprograms and other parts of the work.
146 |
147 | The Corresponding Source need not include anything that users
148 | can regenerate automatically from other parts of the Corresponding
149 | Source.
150 |
151 | The Corresponding Source for a work in source code form is that
152 | same work.
153 |
154 | 2. Basic Permissions.
155 |
156 | All rights granted under this License are granted for the term of
157 | copyright on the Program, and are irrevocable provided the stated
158 | conditions are met. This License explicitly affirms your unlimited
159 | permission to run the unmodified Program. The output from running a
160 | covered work is covered by this License only if the output, given its
161 | content, constitutes a covered work. This License acknowledges your
162 | rights of fair use or other equivalent, as provided by copyright law.
163 |
164 | You may make, run and propagate covered works that you do not
165 | convey, without conditions so long as your license otherwise remains
166 | in force. You may convey covered works to others for the sole purpose
167 | of having them make modifications exclusively for you, or provide you
168 | with facilities for running those works, provided that you comply with
169 | the terms of this License in conveying all material for which you do
170 | not control copyright. Those thus making or running the covered works
171 | for you must do so exclusively on your behalf, under your direction
172 | and control, on terms that prohibit them from making any copies of
173 | your copyrighted material outside their relationship with you.
174 |
175 | Conveying under any other circumstances is permitted solely under
176 | the conditions stated below. Sublicensing is not allowed; section 10
177 | makes it unnecessary.
178 |
179 | 3. Protecting Users' Legal Rights From Anti-Circumvention Law.
180 |
181 | No covered work shall be deemed part of an effective technological
182 | measure under any applicable law fulfilling obligations under article
183 | 11 of the WIPO copyright treaty adopted on 20 December 1996, or
184 | similar laws prohibiting or restricting circumvention of such
185 | measures.
186 |
187 | When you convey a covered work, you waive any legal power to forbid
188 | circumvention of technological measures to the extent such circumvention
189 | is effected by exercising rights under this License with respect to
190 | the covered work, and you disclaim any intention to limit operation or
191 | modification of the work as a means of enforcing, against the work's
192 | users, your or third parties' legal rights to forbid circumvention of
193 | technological measures.
194 |
195 | 4. Conveying Verbatim Copies.
196 |
197 | You may convey verbatim copies of the Program's source code as you
198 | receive it, in any medium, provided that you conspicuously and
199 | appropriately publish on each copy an appropriate copyright notice;
200 | keep intact all notices stating that this License and any
201 | non-permissive terms added in accord with section 7 apply to the code;
202 | keep intact all notices of the absence of any warranty; and give all
203 | recipients a copy of this License along with the Program.
204 |
205 | You may charge any price or no price for each copy that you convey,
206 | and you may offer support or warranty protection for a fee.
207 |
208 | 5. Conveying Modified Source Versions.
209 |
210 | You may convey a work based on the Program, or the modifications to
211 | produce it from the Program, in the form of source code under the
212 | terms of section 4, provided that you also meet all of these conditions:
213 |
214 | a) The work must carry prominent notices stating that you modified
215 | it, and giving a relevant date.
216 |
217 | b) The work must carry prominent notices stating that it is
218 | released under this License and any conditions added under section
219 | 7. This requirement modifies the requirement in section 4 to
220 | "keep intact all notices".
221 |
222 | c) You must license the entire work, as a whole, under this
223 | License to anyone who comes into possession of a copy. This
224 | License will therefore apply, along with any applicable section 7
225 | additional terms, to the whole of the work, and all its parts,
226 | regardless of how they are packaged. This License gives no
227 | permission to license the work in any other way, but it does not
228 | invalidate such permission if you have separately received it.
229 |
230 | d) If the work has interactive user interfaces, each must display
231 | Appropriate Legal Notices; however, if the Program has interactive
232 | interfaces that do not display Appropriate Legal Notices, your
233 | work need not make them do so.
234 |
235 | A compilation of a covered work with other separate and independent
236 | works, which are not by their nature extensions of the covered work,
237 | and which are not combined with it such as to form a larger program,
238 | in or on a volume of a storage or distribution medium, is called an
239 | "aggregate" if the compilation and its resulting copyright are not
240 | used to limit the access or legal rights of the compilation's users
241 | beyond what the individual works permit. Inclusion of a covered work
242 | in an aggregate does not cause this License to apply to the other
243 | parts of the aggregate.
244 |
245 | 6. Conveying Non-Source Forms.
246 |
247 | You may convey a covered work in object code form under the terms
248 | of sections 4 and 5, provided that you also convey the
249 | machine-readable Corresponding Source under the terms of this License,
250 | in one of these ways:
251 |
252 | a) Convey the object code in, or embodied in, a physical product
253 | (including a physical distribution medium), accompanied by the
254 | Corresponding Source fixed on a durable physical medium
255 | customarily used for software interchange.
256 |
257 | b) Convey the object code in, or embodied in, a physical product
258 | (including a physical distribution medium), accompanied by a
259 | written offer, valid for at least three years and valid for as
260 | long as you offer spare parts or customer support for that product
261 | model, to give anyone who possesses the object code either (1) a
262 | copy of the Corresponding Source for all the software in the
263 | product that is covered by this License, on a durable physical
264 | medium customarily used for software interchange, for a price no
265 | more than your reasonable cost of physically performing this
266 | conveying of source, or (2) access to copy the
267 | Corresponding Source from a network server at no charge.
268 |
269 | c) Convey individual copies of the object code with a copy of the
270 | written offer to provide the Corresponding Source. This
271 | alternative is allowed only occasionally and noncommercially, and
272 | only if you received the object code with such an offer, in accord
273 | with subsection 6b.
274 |
275 | d) Convey the object code by offering access from a designated
276 | place (gratis or for a charge), and offer equivalent access to the
277 | Corresponding Source in the same way through the same place at no
278 | further charge. You need not require recipients to copy the
279 | Corresponding Source along with the object code. If the place to
280 | copy the object code is a network server, the Corresponding Source
281 | may be on a different server (operated by you or a third party)
282 | that supports equivalent copying facilities, provided you maintain
283 | clear directions next to the object code saying where to find the
284 | Corresponding Source. Regardless of what server hosts the
285 | Corresponding Source, you remain obligated to ensure that it is
286 | available for as long as needed to satisfy these requirements.
287 |
288 | e) Convey the object code using peer-to-peer transmission, provided
289 | you inform other peers where the object code and Corresponding
290 | Source of the work are being offered to the general public at no
291 | charge under subsection 6d.
292 |
293 | A separable portion of the object code, whose source code is excluded
294 | from the Corresponding Source as a System Library, need not be
295 | included in conveying the object code work.
296 |
297 | A "User Product" is either (1) a "consumer product", which means any
298 | tangible personal property which is normally used for personal, family,
299 | or household purposes, or (2) anything designed or sold for incorporation
300 | into a dwelling. In determining whether a product is a consumer product,
301 | doubtful cases shall be resolved in favor of coverage. For a particular
302 | product received by a particular user, "normally used" refers to a
303 | typical or common use of that class of product, regardless of the status
304 | of the particular user or of the way in which the particular user
305 | actually uses, or expects or is expected to use, the product. A product
306 | is a consumer product regardless of whether the product has substantial
307 | commercial, industrial or non-consumer uses, unless such uses represent
308 | the only significant mode of use of the product.
309 |
310 | "Installation Information" for a User Product means any methods,
311 | procedures, authorization keys, or other information required to install
312 | and execute modified versions of a covered work in that User Product from
313 | a modified version of its Corresponding Source. The information must
314 | suffice to ensure that the continued functioning of the modified object
315 | code is in no case prevented or interfered with solely because
316 | modification has been made.
317 |
318 | If you convey an object code work under this section in, or with, or
319 | specifically for use in, a User Product, and the conveying occurs as
320 | part of a transaction in which the right of possession and use of the
321 | User Product is transferred to the recipient in perpetuity or for a
322 | fixed term (regardless of how the transaction is characterized), the
323 | Corresponding Source conveyed under this section must be accompanied
324 | by the Installation Information. But this requirement does not apply
325 | if neither you nor any third party retains the ability to install
326 | modified object code on the User Product (for example, the work has
327 | been installed in ROM).
328 |
329 | The requirement to provide Installation Information does not include a
330 | requirement to continue to provide support service, warranty, or updates
331 | for a work that has been modified or installed by the recipient, or for
332 | the User Product in which it has been modified or installed. Access to a
333 | network may be denied when the modification itself materially and
334 | adversely affects the operation of the network or violates the rules and
335 | protocols for communication across the network.
336 |
337 | Corresponding Source conveyed, and Installation Information provided,
338 | in accord with this section must be in a format that is publicly
339 | documented (and with an implementation available to the public in
340 | source code form), and must require no special password or key for
341 | unpacking, reading or copying.
342 |
343 | 7. Additional Terms.
344 |
345 | "Additional permissions" are terms that supplement the terms of this
346 | License by making exceptions from one or more of its conditions.
347 | Additional permissions that are applicable to the entire Program shall
348 | be treated as though they were included in this License, to the extent
349 | that they are valid under applicable law. If additional permissions
350 | apply only to part of the Program, that part may be used separately
351 | under those permissions, but the entire Program remains governed by
352 | this License without regard to the additional permissions.
353 |
354 | When you convey a copy of a covered work, you may at your option
355 | remove any additional permissions from that copy, or from any part of
356 | it. (Additional permissions may be written to require their own
357 | removal in certain cases when you modify the work.) You may place
358 | additional permissions on material, added by you to a covered work,
359 | for which you have or can give appropriate copyright permission.
360 |
361 | Notwithstanding any other provision of this License, for material you
362 | add to a covered work, you may (if authorized by the copyright holders of
363 | that material) supplement the terms of this License with terms:
364 |
365 | a) Disclaiming warranty or limiting liability differently from the
366 | terms of sections 15 and 16 of this License; or
367 |
368 | b) Requiring preservation of specified reasonable legal notices or
369 | author attributions in that material or in the Appropriate Legal
370 | Notices displayed by works containing it; or
371 |
372 | c) Prohibiting misrepresentation of the origin of that material, or
373 | requiring that modified versions of such material be marked in
374 | reasonable ways as different from the original version; or
375 |
376 | d) Limiting the use for publicity purposes of names of licensors or
377 | authors of the material; or
378 |
379 | e) Declining to grant rights under trademark law for use of some
380 | trade names, trademarks, or service marks; or
381 |
382 | f) Requiring indemnification of licensors and authors of that
383 | material by anyone who conveys the material (or modified versions of
384 | it) with contractual assumptions of liability to the recipient, for
385 | any liability that these contractual assumptions directly impose on
386 | those licensors and authors.
387 |
388 | All other non-permissive additional terms are considered "further
389 | restrictions" within the meaning of section 10. If the Program as you
390 | received it, or any part of it, contains a notice stating that it is
391 | governed by this License along with a term that is a further
392 | restriction, you may remove that term. If a license document contains
393 | a further restriction but permits relicensing or conveying under this
394 | License, you may add to a covered work material governed by the terms
395 | of that license document, provided that the further restriction does
396 | not survive such relicensing or conveying.
397 |
398 | If you add terms to a covered work in accord with this section, you
399 | must place, in the relevant source files, a statement of the
400 | additional terms that apply to those files, or a notice indicating
401 | where to find the applicable terms.
402 |
403 | Additional terms, permissive or non-permissive, may be stated in the
404 | form of a separately written license, or stated as exceptions;
405 | the above requirements apply either way.
406 |
407 | 8. Termination.
408 |
409 | You may not propagate or modify a covered work except as expressly
410 | provided under this License. Any attempt otherwise to propagate or
411 | modify it is void, and will automatically terminate your rights under
412 | this License (including any patent licenses granted under the third
413 | paragraph of section 11).
414 |
415 | However, if you cease all violation of this License, then your
416 | license from a particular copyright holder is reinstated (a)
417 | provisionally, unless and until the copyright holder explicitly and
418 | finally terminates your license, and (b) permanently, if the copyright
419 | holder fails to notify you of the violation by some reasonable means
420 | prior to 60 days after the cessation.
421 |
422 | Moreover, your license from a particular copyright holder is
423 | reinstated permanently if the copyright holder notifies you of the
424 | violation by some reasonable means, this is the first time you have
425 | received notice of violation of this License (for any work) from that
426 | copyright holder, and you cure the violation prior to 30 days after
427 | your receipt of the notice.
428 |
429 | Termination of your rights under this section does not terminate the
430 | licenses of parties who have received copies or rights from you under
431 | this License. If your rights have been terminated and not permanently
432 | reinstated, you do not qualify to receive new licenses for the same
433 | material under section 10.
434 |
435 | 9. Acceptance Not Required for Having Copies.
436 |
437 | You are not required to accept this License in order to receive or
438 | run a copy of the Program. Ancillary propagation of a covered work
439 | occurring solely as a consequence of using peer-to-peer transmission
440 | to receive a copy likewise does not require acceptance. However,
441 | nothing other than this License grants you permission to propagate or
442 | modify any covered work. These actions infringe copyright if you do
443 | not accept this License. Therefore, by modifying or propagating a
444 | covered work, you indicate your acceptance of this License to do so.
445 |
446 | 10. Automatic Licensing of Downstream Recipients.
447 |
448 | Each time you convey a covered work, the recipient automatically
449 | receives a license from the original licensors, to run, modify and
450 | propagate that work, subject to this License. You are not responsible
451 | for enforcing compliance by third parties with this License.
452 |
453 | An "entity transaction" is a transaction transferring control of an
454 | organization, or substantially all assets of one, or subdividing an
455 | organization, or merging organizations. If propagation of a covered
456 | work results from an entity transaction, each party to that
457 | transaction who receives a copy of the work also receives whatever
458 | licenses to the work the party's predecessor in interest had or could
459 | give under the previous paragraph, plus a right to possession of the
460 | Corresponding Source of the work from the predecessor in interest, if
461 | the predecessor has it or can get it with reasonable efforts.
462 |
463 | You may not impose any further restrictions on the exercise of the
464 | rights granted or affirmed under this License. For example, you may
465 | not impose a license fee, royalty, or other charge for exercise of
466 | rights granted under this License, and you may not initiate litigation
467 | (including a cross-claim or counterclaim in a lawsuit) alleging that
468 | any patent claim is infringed by making, using, selling, offering for
469 | sale, or importing the Program or any portion of it.
470 |
471 | 11. Patents.
472 |
473 | A "contributor" is a copyright holder who authorizes use under this
474 | License of the Program or a work on which the Program is based. The
475 | work thus licensed is called the contributor's "contributor version".
476 |
477 | A contributor's "essential patent claims" are all patent claims
478 | owned or controlled by the contributor, whether already acquired or
479 | hereafter acquired, that would be infringed by some manner, permitted
480 | by this License, of making, using, or selling its contributor version,
481 | but do not include claims that would be infringed only as a
482 | consequence of further modification of the contributor version. For
483 | purposes of this definition, "control" includes the right to grant
484 | patent sublicenses in a manner consistent with the requirements of
485 | this License.
486 |
487 | Each contributor grants you a non-exclusive, worldwide, royalty-free
488 | patent license under the contributor's essential patent claims, to
489 | make, use, sell, offer for sale, import and otherwise run, modify and
490 | propagate the contents of its contributor version.
491 |
492 | In the following three paragraphs, a "patent license" is any express
493 | agreement or commitment, however denominated, not to enforce a patent
494 | (such as an express permission to practice a patent or covenant not to
495 | sue for patent infringement). To "grant" such a patent license to a
496 | party means to make such an agreement or commitment not to enforce a
497 | patent against the party.
498 |
499 | If you convey a covered work, knowingly relying on a patent license,
500 | and the Corresponding Source of the work is not available for anyone
501 | to copy, free of charge and under the terms of this License, through a
502 | publicly available network server or other readily accessible means,
503 | then you must either (1) cause the Corresponding Source to be so
504 | available, or (2) arrange to deprive yourself of the benefit of the
505 | patent license for this particular work, or (3) arrange, in a manner
506 | consistent with the requirements of this License, to extend the patent
507 | license to downstream recipients. "Knowingly relying" means you have
508 | actual knowledge that, but for the patent license, your conveying the
509 | covered work in a country, or your recipient's use of the covered work
510 | in a country, would infringe one or more identifiable patents in that
511 | country that you have reason to believe are valid.
512 |
513 | If, pursuant to or in connection with a single transaction or
514 | arrangement, you convey, or propagate by procuring conveyance of, a
515 | covered work, and grant a patent license to some of the parties
516 | receiving the covered work authorizing them to use, propagate, modify
517 | or convey a specific copy of the covered work, then the patent license
518 | you grant is automatically extended to all recipients of the covered
519 | work and works based on it.
520 |
521 | A patent license is "discriminatory" if it does not include within
522 | the scope of its coverage, prohibits the exercise of, or is
523 | conditioned on the non-exercise of one or more of the rights that are
524 | specifically granted under this License. You may not convey a covered
525 | work if you are a party to an arrangement with a third party that is
526 | in the business of distributing software, under which you make payment
527 | to the third party based on the extent of your activity of conveying
528 | the work, and under which the third party grants, to any of the
529 | parties who would receive the covered work from you, a discriminatory
530 | patent license (a) in connection with copies of the covered work
531 | conveyed by you (or copies made from those copies), or (b) primarily
532 | for and in connection with specific products or compilations that
533 | contain the covered work, unless you entered into that arrangement,
534 | or that patent license was granted, prior to 28 March 2007.
535 |
536 | Nothing in this License shall be construed as excluding or limiting
537 | any implied license or other defenses to infringement that may
538 | otherwise be available to you under applicable patent law.
539 |
540 | 12. No Surrender of Others' Freedom.
541 |
542 | If conditions are imposed on you (whether by court order, agreement or
543 | otherwise) that contradict the conditions of this License, they do not
544 | excuse you from the conditions of this License. If you cannot convey a
545 | covered work so as to satisfy simultaneously your obligations under this
546 | License and any other pertinent obligations, then as a consequence you may
547 | not convey it at all. For example, if you agree to terms that obligate you
548 | to collect a royalty for further conveying from those to whom you convey
549 | the Program, the only way you could satisfy both those terms and this
550 | License would be to refrain entirely from conveying the Program.
551 |
552 | 13. Use with the GNU Affero General Public License.
553 |
554 | Notwithstanding any other provision of this License, you have
555 | permission to link or combine any covered work with a work licensed
556 | under version 3 of the GNU Affero General Public License into a single
557 | combined work, and to convey the resulting work. The terms of this
558 | License will continue to apply to the part which is the covered work,
559 | but the special requirements of the GNU Affero General Public License,
560 | section 13, concerning interaction through a network will apply to the
561 | combination as such.
562 |
563 | 14. Revised Versions of this License.
564 |
565 | The Free Software Foundation may publish revised and/or new versions of
566 | the GNU General Public License from time to time. Such new versions will
567 | be similar in spirit to the present version, but may differ in detail to
568 | address new problems or concerns.
569 |
570 | Each version is given a distinguishing version number. If the
571 | Program specifies that a certain numbered version of the GNU General
572 | Public License "or any later version" applies to it, you have the
573 | option of following the terms and conditions either of that numbered
574 | version or of any later version published by the Free Software
575 | Foundation. If the Program does not specify a version number of the
576 | GNU General Public License, you may choose any version ever published
577 | by the Free Software Foundation.
578 |
579 | If the Program specifies that a proxy can decide which future
580 | versions of the GNU General Public License can be used, that proxy's
581 | public statement of acceptance of a version permanently authorizes you
582 | to choose that version for the Program.
583 |
584 | Later license versions may give you additional or different
585 | permissions. However, no additional obligations are imposed on any
586 | author or copyright holder as a result of your choosing to follow a
587 | later version.
588 |
589 | 15. Disclaimer of Warranty.
590 |
591 | THERE IS NO WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY
592 | APPLICABLE LAW. EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT
593 | HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY
594 | OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO,
595 | THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
596 | PURPOSE. THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE PROGRAM
597 | IS WITH YOU. SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF
598 | ALL NECESSARY SERVICING, REPAIR OR CORRECTION.
599 |
600 | 16. Limitation of Liability.
601 |
602 | IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
603 | WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MODIFIES AND/OR CONVEYS
604 | THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY
605 | GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE
606 | USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF
607 | DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD
608 | PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS),
609 | EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF
610 | SUCH DAMAGES.
611 |
612 | 17. Interpretation of Sections 15 and 16.
613 |
614 | If the disclaimer of warranty and limitation of liability provided
615 | above cannot be given local legal effect according to their terms,
616 | reviewing courts shall apply local law that most closely approximates
617 | an absolute waiver of all civil liability in connection with the
618 | Program, unless a warranty or assumption of liability accompanies a
619 | copy of the Program in return for a fee.
620 |
621 | END OF TERMS AND CONDITIONS
622 |
623 | How to Apply These Terms to Your New Programs
624 |
625 | If you develop a new program, and you want it to be of the greatest
626 | possible use to the public, the best way to achieve this is to make it
627 | free software which everyone can redistribute and change under these terms.
628 |
629 | To do so, attach the following notices to the program. It is safest
630 | to attach them to the start of each source file to most effectively
631 | state the exclusion of warranty; and each file should have at least
632 | the "copyright" line and a pointer to where the full notice is found.
633 |
634 |
635 | Copyright (C)
636 |
637 | This program is free software: you can redistribute it and/or modify
638 | it under the terms of the GNU General Public License as published by
639 | the Free Software Foundation, either version 3 of the License, or
640 | (at your option) any later version.
641 |
642 | This program is distributed in the hope that it will be useful,
643 | but WITHOUT ANY WARRANTY; without even the implied warranty of
644 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
645 | GNU General Public License for more details.
646 |
647 | You should have received a copy of the GNU General Public License
648 | along with this program. If not, see .
649 |
650 | Also add information on how to contact you by electronic and paper mail.
651 |
652 | If the program does terminal interaction, make it output a short
653 | notice like this when it starts in an interactive mode:
654 |
655 | Copyright (C)
656 | This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
657 | This is free software, and you are welcome to redistribute it
658 | under certain conditions; type `show c' for details.
659 |
660 | The hypothetical commands `show w' and `show c' should show the appropriate
661 | parts of the General Public License. Of course, your program's commands
662 | might be different; for a GUI interface, you would use an "about box".
663 |
664 | You should also get your employer (if you work as a programmer) or school,
665 | if any, to sign a "copyright disclaimer" for the program, if necessary.
666 | For more information on this, and how to apply and follow the GNU GPL, see
667 | .
668 |
669 | The GNU General Public License does not permit incorporating your program
670 | into proprietary programs. If your program is a subroutine library, you
671 | may consider it more useful to permit linking proprietary applications with
672 | the library. If this is what you want to do, use the GNU Lesser General
673 | Public License instead of this License. But first, please read
674 | .
675 |
--------------------------------------------------------------------------------
/NAMESPACE:
--------------------------------------------------------------------------------
1 | # Generated by roxygen2: do not edit by hand
2 |
3 | export("%>%")
4 | export(conRelPlot)
5 | export(itemDist)
6 | export(itemInfoPlot)
7 | export(itemfitPlot)
8 | export(itempersonMap)
9 | export(personDist)
10 | export(personfitPlot)
11 | export(scaleCharPlot)
12 | export(sim_irt)
13 | export(summaryPlot)
14 | export(testInfoCompare)
15 | export(testInfoPlot)
16 | export(tracePlot)
17 | import(dplyr)
18 | import(ggplot2)
19 | import(mirt)
20 | import(tidyr)
21 | importFrom(magrittr,"%>%")
22 |
--------------------------------------------------------------------------------
/R/.DS_Store:
--------------------------------------------------------------------------------
https://raw.githubusercontent.com/masurp/ggmirt/4cfa1069f12409e0d8420ec67468a7f32351d0b3/R/.DS_Store
--------------------------------------------------------------------------------
/R/conRelPlot.r:
--------------------------------------------------------------------------------
1 | #' Plotting conditional reliability
2 | #'
3 | #' This function takes a fitted mirt-model and visualizes a conditional reliability curve. Heavily inspired by code from Phil Chalmers (author or 'mirt')
4 | #'
5 | #'
6 | #' @param model an object of class `SingleGroupClass` returned by the function `mirt()`.
7 | #' @param theta_range range to be shown on the x-axis
8 | #' @param color color of the line
9 | #' @param title title for the plot (defaults to "Conditional Reliability")
10 | #'
11 | #' @return a ggplot
12 | #' @import ggplot2
13 | #' @import dplyr
14 | #' @import tidyr
15 | #' @import mirt
16 | #' @export
17 | #'
18 | #' @examples
19 | #' library(mirt)
20 | #' library(ggmirt)
21 | #' data <- expand.table(LSAT7)
22 | #' (mod <- mirt(data, 1))
23 | #'
24 | #' conRelPlot(mod)
25 | conRelPlot <- function(model,
26 | theta_range = c(-4,4),
27 | color = "red",
28 | title = "Conditional Reliability") {
29 |
30 | # helper functions
31 |
32 | computeItemtrace <- function(pars, Theta, itemloc, offterm = matrix(0L, 1L, length(itemloc)-1L),
33 | CUSTOM.IND, pis = NULL){
34 | if(is.null(pis)){
35 | itemtrace <- .Call('computeItemTrace', pars, Theta, itemloc, offterm)
36 | if(length(CUSTOM.IND)){
37 | for(i in CUSTOM.IND)
38 | itemtrace[,itemloc[i]:(itemloc[i+1L] - 1L)] <- ProbTrace(pars[[i]], Theta=Theta)
39 | }
40 | } else {
41 | tmp_itemtrace <- vector('list', length(pis))
42 | for(g in seq_len(length(pis))){
43 | tmp_itemtrace[[g]] <- .Call('computeItemTrace', pars[[g]]@ParObjects$pars, Theta, itemloc, offterm)
44 | if(length(CUSTOM.IND)){
45 | for(i in CUSTOM.IND)
46 | tmp_itemtrace[[g]][,itemloc[i]:(itemloc[i+1L] - 1L)] <- ProbTrace(pars[[g]]@ParObjects$pars[[i]], Theta=Theta)
47 | }
48 | }
49 | itemtrace <- do.call(rbind, tmp_itemtrace)
50 | }
51 | return(itemtrace)
52 | }
53 |
54 | ExtractGroupPars <- function(x){
55 | if(x@itemclass < 0L) return(list(gmeans=0, gcov=matrix(1)))
56 | nfact <- x@nfact
57 | gmeans <- x@par[seq_len(nfact)]
58 | phi_matches <- grepl("PHI", x@parnames)
59 | if (x@dentype == "Davidian") {
60 | phi <- x@par[phi_matches]
61 | tmp <- x@par[-c(seq_len(nfact), which(phi_matches))]
62 | gcov <- matrix(0, nfact, nfact)
63 | gcov[lower.tri(gcov, diag=TRUE)] <- tmp
64 | gcov <- makeSymMat(gcov)
65 | return(list(gmeans=gmeans, gcov=gcov, phi=phi))
66 | } else {
67 | par <- x@par
68 | if(x@dentype == "mixture") par <- par[-length(par)] # drop pi
69 | tmp <- par[-seq_len(nfact)]
70 | gcov <- matrix(0, nfact, nfact)
71 | gcov[lower.tri(gcov, diag=TRUE)] <- tmp
72 | gcov <- makeSymMat(gcov)
73 | return(list(gmeans=gmeans, gcov=gcov))
74 | }
75 | }
76 |
77 | makeSymMat <- function(mat){
78 | if(ncol(mat) > 1L){
79 | mat[is.na(mat)] <- 0
80 | mat <- mat + t(mat) - diag(diag(mat))
81 | }
82 | mat
83 | }
84 |
85 | # Actual computation
86 | nfact <- model@Model$nfact
87 | J <- model@Data$nitems
88 | theta <- seq(theta_range[1],theta_range[2], by = .01)
89 | ThetaFull <- Theta <- thetaComb(theta, nfact)
90 | info <- testinfo(model, ThetaFull)
91 | itemtrace <- computeItemtrace(model@ParObjects$pars, ThetaFull, model@Model$itemloc,
92 | CUSTOM.IND=model@Internals$CUSTOM.IND)
93 | mins <- model@Data$mins
94 | maxs <- extract.mirt(model, 'K') + mins - 1
95 | gp <- ExtractGroupPars(model@ParObjects$pars[[J+1]])
96 | score <- c()
97 | for(i in 1:J)
98 | score <- c(score, (0:(model@Data$K[i]-1) + mins[i]) * (i %in% c(1:J)))
99 | score <- matrix(score, nrow(itemtrace), ncol(itemtrace), byrow = TRUE)
100 | plt <- data.frame(cbind(info,score=rowSums(score*itemtrace),Theta=Theta))
101 | colnames(plt) <- c("info", "score", "Theta")
102 | plt$SE <- 1 / sqrt(plt$info)
103 | plt$rxx <- plt$info / (plt$info + 1/gp$gcov[1L,1L])
104 |
105 | ggplot(plt, aes(x = Theta, y = rxx)) +
106 | geom_line(color = color) +
107 | ylim(0, 1) +
108 | theme_minimal() +
109 | labs(title = title, x = expression(theta), y = expression(r[xx](theta)))
110 |
111 | }
112 |
--------------------------------------------------------------------------------
/R/itemDistribution.r:
--------------------------------------------------------------------------------
1 | #' Item difficulty distribution
2 | #'
3 | #' This function requires a fitted mirt-model of class `SingleGroupClass` to visualize item difficulty distribution. Currently only works for unidimensional models.
4 | #'
5 | #' @param model an object of class `SingleGroupClass` returned by the function `mirt()`.
6 | #' @param ... any argument passed to `geom_point()`
7 | #'
8 | #' @return a ggplot object.
9 | #' @import ggplot2
10 | #' @import dplyr
11 | #' @import tidyr
12 | #' @import mirt
13 | #' @export
14 | #'
15 | #' @examples
16 | #' # Loading packages
17 | #' library(mirt)
18 | #' library(ggmirt)
19 | #'
20 | #' # Getting data
21 | #' data <- expand.table(LSAT7)
22 | #'
23 | #' # Fitting a model
24 | #' (mod <- mirt(data, 1))
25 | #'
26 | #' # Simple plot
27 | #' itemDist(mod)
28 | #'
29 | #' # Customized plot
30 | #' itemDist(mod, size = 3, shape = 17, color = "blue")
31 | #'
32 | itemDist <- function(model,
33 | theta_range = c(-4, 4),
34 | ...) {
35 |
36 | item.params <- mirt::coef(model, IRTpars = TRUE, simplify = TRUE) %>%
37 | as.data.frame %>%
38 | tibble::rownames_to_column("items")
39 |
40 | p <- item.params %>%
41 | mutate(items = forcats::fct_reorder(items, items.b)) %>%
42 | ggplot(aes(y = items, x = items.b)) +
43 | geom_point(...)
44 |
45 | p + xlim(theta_range) + theme_minimal() + labs(x = expression(theta), y = "")
46 | }
47 |
48 |
--------------------------------------------------------------------------------
/R/itemInfoPlot.r:
--------------------------------------------------------------------------------
1 | #' Plotting item information curves
2 | #'
3 | #' This function takes a fitted mirt-model and visualizes items information curves.
4 | #'
5 | #'
6 | #' @param model an object of class `SingleGroupClass` returned by the function `mirt()`.
7 | #' @param items numerical vector indicating which items to plot.
8 | #' @param facet Should all items be shown in one plot, or each item received its individal facet?
9 | #' @param theta_range range to be shown on the x-axis
10 | #' @param title title for the plot (defaults to "Item Characteristic Curves")
11 | #'
12 | #' @return a ggplot
13 | #' @import ggplot2
14 | #' @import dplyr
15 | #' @import tidyr
16 | #' @import mirt
17 | #' @export
18 | #'
19 | #' @examples
20 | #' library(mirt)
21 | #' library(ggmirt)
22 | #' data <- expand.table(LSAT7)
23 | #' (mod <- mirt(data, 1))
24 | #'
25 | #' itemInfoPlot(mod)
26 | #'
27 | itemInfoPlot <- function(model,
28 | items = NULL,
29 | facet = FALSE,
30 | title = "Item Information Curves",
31 | theta_range = c(-4,4),
32 | legend = FALSE) {
33 |
34 | data <- model@Data$data %>% as.data.frame
35 |
36 | theta_range = seq(theta_range[1], theta_range[2], by = .01)
37 |
38 | test <- NULL
39 | for(i in 1:length(data)){
40 | theta <- matrix(theta_range)
41 | test[[i]] <- testinfo(model, Theta = theta, which.items = i)
42 | }
43 |
44 | if (!is.null(items)) {
45 | test <- test[items]
46 | }
47 |
48 | names(test) <- paste('item', 1:length(test))
49 | test <- as.data.frame(test, theta) %>%
50 | tibble::rownames_to_column("theta") %>%
51 | gather(key, value, -theta) %>%
52 | mutate(theta = as.numeric(theta))
53 |
54 | # final plot
55 | if(isFALSE(facet)) {
56 | p <- ggplot(test, aes(theta, value, colour = key)) +
57 | geom_line() +
58 | labs(x = expression(theta),
59 | y = expression(I(theta)),
60 | title = title,
61 | color = "Item") +
62 | theme_minimal() +
63 | scale_color_brewer(palette = 7)
64 |
65 | if(isFALSE(legend)) {
66 | p <- p + guides(color = FALSE)
67 | # change guides(color = "none")
68 | }
69 |
70 | } else {
71 | p <- ggplot(test, aes(theta, value)) +
72 | geom_line() +
73 | facet_wrap(~key) +
74 | labs(x = expression(theta),
75 | y = expression(I(theta)),
76 | title = title) +
77 | theme_minimal()
78 | }
79 | return(p)
80 | }
81 |
82 |
83 |
--------------------------------------------------------------------------------
/R/itemfitPlot.r:
--------------------------------------------------------------------------------
1 | #' Plotting itemfit estimates
2 | #'
3 | #' This function takes a fitted mirt-model and visualizes item infit and outfit estimates. The function builds on `mirt::itemfit()`. Currently only supported `fact_stats = "infit"`.
4 | #'
5 | #'
6 | #' @param model an object of class `SingleGroupClass` returned by the function `mirt()`.
7 | #' @param fit_stats a character vector indicating which fit statistics should be computed. See `mirt::infit()` for supported inputs.
8 | #' @param color color of the item points.
9 | #' @param shape shape of the item points
10 | #' @param title title for the plot (defaults to "Item Infit and Outfit Statistics")
11 | #'
12 | #' @return a ggplot
13 | #'
14 | #' @references \itemize{
15 | #' \item Linacre JM. (2002). What do Infit and Outfit, Mean-square and Standardized mean? Rasch Measurement Transactions, 16(2), p.878. https://www.rasch.org/rmt/rmt162f.htm
16 | #' }
17 | #'
18 | #' @import ggplot2
19 | #' @import dplyr
20 | #' @import tidyr
21 | #' @import mirt
22 | #' @export
23 | #'
24 | #' @examples
25 | #' library(mirt)
26 | #' library(ggmirt)
27 | #' data <- expand.table(LSAT7)
28 | #' (mod <- mirt(data, 1))
29 | #'
30 | #' itemfitPlot(mod, fit_stats = "infit")
31 | #'
32 | itemfitPlot <- function(model,
33 | fit_stats = "infit",
34 | color = "red",
35 | shape = 17,
36 | title = "Item Infit and Outfit Statistics",
37 | ...) {
38 |
39 |
40 | fit <- mirt::itemfit(model, fit_stats = fit_stats, ...)
41 |
42 | if("infit" %in% names(fit)) {
43 | fit %>%
44 | select(item, infit, outfit) %>%
45 | gather(key, value, -item) %>%
46 | ggplot(aes(x = item, y = value)) +
47 | geom_point(size = 3, color = color, shape = shape) +
48 | geom_line() +
49 | geom_hline(yintercept = .5, color = "darkgrey", linetype = "dashed") +
50 | geom_hline(yintercept = 1, color = "darkgrey") +
51 | geom_hline(yintercept = 1.5, color = "darkgrey", linetype = "dashed") +
52 | scale_y_continuous(breaks = c(.5, 1, 1.5), limits = c(0, 2)) +
53 | facet_grid(~key) +
54 | coord_flip() +
55 | theme_minimal() +
56 | labs(y = "", x = "", caption = "Note: Items with values within 0.5 and 1.5 are considered to be productive for measurement.",
57 | title = title)
58 | }
59 | }
60 |
61 |
62 |
63 |
--------------------------------------------------------------------------------
/R/itempersonmap.r:
--------------------------------------------------------------------------------
1 | #' Visualize item person map and scale properties based on Rasch model
2 | #'
3 | #' This function takes a fitted mirt-model and visualizes and plots item-person-map (also known as Kernel-Density Plots or Wright maps) on the left, and add a scale characteristic curve, scale information curve, and a marginal reliability curve on the right.
4 | #'
5 | #'
6 | #' @param model an object of class `SingleGroupClass` returned by the function `mirt()`.
7 | #' @param limits range to be shown on the x-axis
8 | #' @param title title for the plot (defaults to "Item-Person-Map")
9 | #' @param margin margins around the top figure. Sometimes one might want to adjust this.
10 | #' @param density logical value indicating whether a smoothed density curve or a standard histogram should be plotted.
11 | #' @param color color of the geoms, defaults to "red".
12 | #' @param shape can be used to change the shape of the geom, defaults to triangles (17).
13 | #' @param size size of the geom, default to 3.
14 | #' @param theme any ggplot theme.
15 | #' @param ... any argument passed to `geom_point()`.
16 | #'
17 | #' @return a plot grid as returned by `cowplot::plot_grid()`
18 | #' @import ggplot2
19 | #' @import dplyr
20 | #' @import tidyr
21 | #' @import mirt
22 | #' @export
23 | #'
24 | #' @examples
25 | #' library(mirt)
26 | #' library(ggmirt)
27 | #' data <- expand.table(LSAT7)
28 | #' (mod <- mirt(data, 1))
29 | #'
30 | #' itempersonMap(mod)
31 | #'
32 | itempersonMap <- function(model,
33 | theta_range = c(-4,4),
34 | title = "Item Person Map",
35 | margin = c(1,0,-1.5,0),
36 | density = FALSE,
37 | color = "red",
38 | shape = 17,
39 | size = 3,
40 | theme = theme_minimal(),
41 | ...) {
42 |
43 | p1 <- personDist(model, theta_range = theta_range, density = density) +
44 | theme +
45 | theme(plot.margin = unit(margin,"cm")) +
46 | labs(title = title)
47 | p2 <- itemDist(model, theta_range = theta_range, shape = shape, color = color, size = size, ...) +
48 | theme
49 |
50 |
51 | p <- cowplot::plot_grid(p1, p2,
52 | nrow = 2,
53 | rel_heights = c(1.5,2.5),
54 | align = "hv",
55 | axis = "tlbr")
56 |
57 | return(p)
58 | }
59 |
60 |
--------------------------------------------------------------------------------
/R/personDistribution.r:
--------------------------------------------------------------------------------
1 | #' Person parameter distribution
2 | #'
3 | #' This function requires a fitted mirt-model of class `SingleGroupClass` to visualize a person parameter distribution (theta levels in the studied population). The resulting ggplot can be further customized (e.g., with regard to theme, labels, etc.). It works with both uni- and multidimensional models.
4 | #'
5 | #' @param model an object of class `SingleGroupClass` returned by the function `mirt()`.
6 | #' @param density logical value indicating whether a smoothed density curve or a standard histogram should be plotted.
7 | #' @param bins number of bins to be plotted in the histogram
8 | #'
9 | #' @return a ggplot object.
10 | #' @import ggplot2
11 | #' @import dplyr
12 | #' @import tidyr
13 | #' @import mirt
14 | #' @export
15 | #'
16 | #' @examples
17 | #' # Loading packages
18 | #' library(mirt)
19 | #' library(ggmirt)
20 | #'
21 | #' # Getting data
22 | #' data <- expand.table(LSAT7)
23 | #'
24 | #' # Fitting a model
25 | #' (mod <- mirt(data, 1))
26 | #'
27 | #' # Simple plot
28 | #' personDist(mod)
29 | #' personDist(mod, density = TRUE)
30 | #'
31 | #' # Customized plot
32 | #' personDist(mod, theta_range = c(-3, 3), bins = 10) +
33 | #' theme_classic()
34 | personDist <- function(model,
35 | theta_range = c(-4, 4),
36 | density = FALSE,
37 | bins = 35) {
38 |
39 | person.params <- fscores(model, QMC = TRUE) %>%
40 | as.data.frame()
41 |
42 | if(length(person.params) != 1) {
43 | p <- person.params %>%
44 | tidyr::pivot_longer(names(.), names_to = "dimension") %>%
45 | ggplot(aes(x = value, fill = dimension))
46 |
47 | } else {
48 |
49 | p <- person.params %>%
50 | pivot_longer(names(.), names_to = "dimension") %>%
51 | ggplot(aes(x = value, fill = dimension)) +
52 | guides(fill = "none")
53 | }
54 |
55 | if(isTRUE(density)) {
56 |
57 | p <- p + geom_density()
58 |
59 | } else {
60 |
61 | p <- p + geom_histogram(bins = bins, color = "white")
62 | }
63 |
64 |
65 | p + xlim(theta_range) + theme_minimal() + labs(x = expression(theta))
66 |
67 | }
68 |
--------------------------------------------------------------------------------
/R/personfitPlot.r:
--------------------------------------------------------------------------------
1 | #' Plotting personfit estimates
2 | #'
3 | #' This function takes a fitted mirt-model and visualizes person infit and outfit estimates. The function builds on `mirt::itemfit()`. The basic idea is to visualize how many individuals in the sample do not show a response pattern that aligns with the suggested model. At best, the number of non-fitting response patterns is low (e.g., < 5%).
4 | #'
5 | #'
6 | #' @param model an object of class `SingleGroupClass` returned by the function `mirt()`.
7 | #' @param std logical value indicating whether standardized or non-standardized infit or outfit estimates should be used (leads to different cut-off values).
8 | #' @param title title for the plot (defaults to "Person Infit and Outfit Statistics")
9 | #'
10 | #' @return a ggplot
11 | #'
12 | #' @references \itemize{
13 | #' \item Linacre JM. (2002). What do Infit and Outfit, Mean-square and Standardized mean? Rasch Measurement Transactions, 16(2), p.878. https://www.rasch.org/rmt/rmt162f.htm
14 | #' }
15 | #'
16 | #' @import ggplot2
17 | #' @import dplyr
18 | #' @import tidyr
19 | #' @import mirt
20 | #' @export
21 | #'
22 | #' @examples
23 | #' library(mirt)
24 | #' library(ggmirt)
25 | #' data <- expand.table(LSAT7)
26 | #' (mod <- mirt(data, 1))
27 | #'
28 | #' personfitPlot(mod, std = F)
29 | #'
30 | personfitPlot <- function(model,
31 | std = TRUE,
32 | title = "Person Infit and Outfit Statistics"){
33 |
34 |
35 | if(isTRUE(std)) {
36 |
37 | fit <- mirt::personfit(model) %>%
38 | dplyr::select(z.infit, z.outfit) %>%
39 | gather(key, value) %>%
40 | mutate(color_diff = ifelse(value < -1.96, "red",
41 | ifelse(value > 1.96, "red", "grey")))
42 |
43 | limits <- c(-1.96, 0, 1.96)
44 | } else {
45 |
46 | fit <- mirt::personfit(model) %>%
47 | dplyr::select(infit, outfit) %>%
48 | gather(key, value) %>%
49 | mutate(color_diff = ifelse(value < .5, "red",
50 | ifelse(value > 1.5, "red", "grey")))
51 | limits <- c(.5, 1, 1.5)
52 | }
53 |
54 | fit %>%
55 | ggplot(aes(x = value, fill = color_diff)) +
56 | geom_histogram(color = "white") +
57 | geom_vline(xintercept = limits[3], color = "darkgrey", linetype = "dashed") +
58 | geom_vline(xintercept = limits[2], color = "darkgrey") +
59 | geom_vline(xintercept = limits[1], color = "darkgrey", linetype = "dashed") +
60 | facet_wrap(~key) +
61 | theme_minimal() +
62 | theme(legend.position = "none") +
63 | labs(x = "",
64 | y = "",
65 | title = title)
66 | }
67 |
--------------------------------------------------------------------------------
/R/scaleCharPlot.r:
--------------------------------------------------------------------------------
1 | #' Scale Characteristic Curve
2 | #'
3 | #' Once model-based theta score estimates are computed, it often is of interest to transform those estimates into the original scale metric. A scale characteristic function provides a means of transforming estimated theta scores to expected true scores in the original scale metric. This transformation back into the original scale metric provides a more familiar frame of reference for interpreting scores. This function provides a visualization for this transformation.
4 | #'
5 | #' @param model an object of class `SingleGroupClass` returned by the function `mirt()`.
6 | #' @param theta_range range to be shown on the x-axis
7 | #' @param color color of the line
8 | #' @param title title for the plot (defaults to "Person Infit and Outfit Statistics")
9 | #'
10 | #' @return a ggplot
11 | #'
12 | #' @import ggplot2
13 | #' @import dplyr
14 | #' @import tidyr
15 | #' @import mirt
16 | #' @export
17 | #'
18 | #' @examples
19 | #' library(mirt)
20 | #' library(ggmirt)
21 | #' data <- expand.table(LSAT7)
22 | #' (mod <- mirt(data, 1))
23 | #'
24 | #' scaleCharPlot(mod)
25 | #'
26 | scaleCharPlot <- function(model,
27 | theta_range = c(-4, 4),
28 | color = "red",
29 | title = "Scale Characteristic Curve") {
30 |
31 | theta <- seq(theta_range[1], theta_range[2], by = .01)
32 | score <- expected.test(model, matrix(theta))
33 | n.items <- model@Data$nitems
34 |
35 | d <- data.frame(theta, score)
36 | p <- ggplot(d, aes(x = theta, y = score)) +
37 | geom_line(color = color) +
38 | theme_minimal() +
39 | labs(x = expression(theta), y = expression(T(theta)),
40 | title = title)
41 |
42 | return(p)
43 | }
44 |
45 |
46 |
--------------------------------------------------------------------------------
/R/sim_irt.r:
--------------------------------------------------------------------------------
1 | #' Helper function to simulate IRT data
2 | #'
3 | #' Function to simulate data that can be used to fit IRT models.
4 | #'
5 | #' @param n.obs Number of observations that should be included in the data set
6 | #' @param n.items Number of items that should be simulated
7 | #' @param discrimination Standard deviation on the log scale
8 | #' @param seed Seed for the random number generation process
9 | #' @param cut Either "random" for a randomized transformation of the model probability matrix into the model 0-1 matrix or an integer value between 0 and 1.
10 | #'
11 | #' @return a tibble
12 | #' @export
13 | #'
14 | #' @examples
15 | #' library(ggmirt)
16 | #'
17 | #' sim_irt(n.obs = 200, n.items = 10)
18 | #'
19 | sim_irt <- function(n.obs = 100,
20 | n.items = 10,
21 | discrimination = 0,
22 | seed = NULL,
23 | cut = "random") {
24 |
25 | # Get item difficulty distribution
26 | if (length(n.items) == 1) {
27 | if (!is.null(seed))
28 | set.seed(seed)
29 |
30 | difficulty <- rnorm(n.items)
31 | no.items <- n.items
32 |
33 | } else {
34 |
35 | difficulty <- n.items
36 | no.items <- length(n.items)
37 | }
38 |
39 | # Get person ability distribution
40 | if (length(n.obs) == 1) {
41 | if (!is.null(seed))
42 | set.seed(seed)
43 |
44 | ability <- rnorm(n.obs)
45 | no.obs <- n.obs
46 |
47 | } else {
48 |
49 | ability <- n.obs
50 | no.obs <- length(n.obs)
51 | }
52 |
53 | # Draw discrimination distribution if needed
54 | if (length(discrimination) > 1) {
55 | alpha <- discrimination
56 |
57 | } else {
58 |
59 | if (!is.null(seed))
60 | set.seed(seed)
61 |
62 | alpha <- rlnorm(no.items, 0, sdlog = discrimination)
63 | }
64 |
65 | # Create empty matrix
66 | psolve <- matrix(0, no.obs, no.items)
67 |
68 |
69 | # Simulate response pattern
70 | for (i in 1:no.obs) for (j in 1:no.items) psolve[i, j] <- exp(alpha[j] * (ability[i] - difficulty[j]))/(1 + exp(alpha[j] * (ability[i] - difficulty[j])))
71 |
72 | # Transform into binary items
73 | if (cut == "random") {
74 | if (!is.null(seed))
75 | set.seed(seed)
76 |
77 | m <- (matrix(runif(no.items * no.obs), no.obs, no.items) < psolve) * 1
78 |
79 | } else {
80 |
81 | m <- (cut < psolve) * 1
82 | }
83 |
84 | d <- as_tibble(m)
85 |
86 | return(d)
87 | }
88 |
89 |
90 |
--------------------------------------------------------------------------------
/R/summaryPlot.r:
--------------------------------------------------------------------------------
1 | #' A quick summary of IRT analyses
2 | #'
3 | #' This function is essentially just a wrapper around several functions in this package and produces a summary of the most important aspects of an IRT model, including an item-person-map,test information curve, scale characteristic curve, and conditional reliability.
4 | #'
5 | #' @param model an object of class `SingleGroupClass` returned by the function `mirt()`.
6 | #' @param theta_range range to be shown on the x-axis
7 | #' @param adj_factor adjustment factor for properly overlaying information and standard error.
8 | #'
9 | #' @return a plot grid as returned by `cowplot::ggdraw()`
10 | #' @import ggplot2
11 | #' @import dplyr
12 | #' @import tidyr
13 | #' @import mirt
14 | #' @export
15 | #'
16 | #' @examples
17 | #' library(mirt)
18 | #' library(ggmirt)
19 | #'
20 | #' # Simulate some data
21 | #' data <- sim_irt(500, 10, seed = 123)
22 | #'
23 | #' # Run IRT model with mirt
24 | #' mod <- mirt(data, 1, itemtype = "2PL", verbose = FALSE)
25 | #'
26 | #' summaryPlot(mod, theta_range = c(-4.5, 3.5), adj_factor = 1.5)
27 | #'
28 | summaryPlot <- function(model,
29 | theta_range = c(-4, 4),
30 | adj_factor = .05) {
31 |
32 | # Get number of items
33 | J <- model@Data$nitems
34 |
35 | # Person parameter distribution
36 | p1 <- personDist(model, theta_range = theta_range) +
37 | labs(title = "Item Person Map")
38 |
39 | # Item difficulty distribution
40 | p2 <- itemDist(model, theta_range = theta_range, shape = 17, color = "red")
41 |
42 | # Change item labelling if no. items > 10
43 | if(J > 10) {
44 | p2 <- p2 +
45 | geom_text(aes(label = items), nudge_x = .75, color = "darkgrey", size = 2, check_overlap = T) +
46 | theme(axis.text.y = element_blank(),
47 | panel.grid.major.y = element_blank())
48 | }
49 |
50 | # Scale Characteristic Curve
51 | p3 <- scaleCharPlot(model, theta_range = theta_range)
52 |
53 | # Test information curve
54 | p4 <- testInfoPlot(model, theta_range = theta_range, adj_factor = adj_factor)
55 |
56 | # Conditional reliability curve
57 | p5 <- conRelPlot(model, theta_range = theta_range)
58 |
59 | # Bind together
60 | p <- ggpubr::ggarrange(ggpubr::ggarrange(p1, p2,
61 | ncol = 1,
62 | align = "hv",
63 | heights = c(1,2)),
64 | ggpubr::ggarrange(p4, p3, p5,
65 | ncol = 1,
66 | align = "hv",
67 | heights = c(1.25, 1, 1)),
68 | ncol = 2)
69 |
70 |
71 | return(p)
72 |
73 | }
74 |
75 |
--------------------------------------------------------------------------------
/R/testInfoCompare.r:
--------------------------------------------------------------------------------
1 | #' Comparing test information curves of parallel tests
2 | #'
3 | #' This function takes two fitted mirt-model and visualizes test their test information curves on top of each other. This can be helpful for finding parallel tests.
4 | #'
5 | #'
6 | #' @param model1 an object of class `SingleGroupClass` returned by the function `mirt()`.
7 | #' @param model2 an object of class `SingleGroupClass`
8 | #' @param title title for the plot
9 | #' @param subtitle subtitle for the plot
10 | #'
11 | #' @return a ggplot
12 | #' @import ggplot2
13 | #' @import dplyr
14 | #' @import tidyr
15 | #' @import mirt
16 | #' @export
17 | #'
18 | #' @examples
19 | #' library(mirt)
20 | #' library(ggmirt)
21 | #' data <- expand.table(LSAT7)
22 | #' (mod1 <- mirt(data, 1))
23 | #' (mod2 <- mirt(data[,1:4], 1))
24 | #'
25 | #' testInfoCompare(mod1, mod2)
26 | #'
27 | testInfoCompare <- function(model1, model2,
28 | theta_range = c(-4,4),
29 | title = "Parallel Tests",
30 | subtitle = "Test Information Curves") {
31 |
32 | theta_range = seq(theta_range[1], theta_range[2], by = .01)
33 |
34 | Theta <- matrix(theta_range)
35 | information1 <- testinfo(model1, Theta)
36 | information2 <- testinfo(model2, Theta)
37 |
38 | p <- data.frame(Theta, information1, information2) %>%
39 | gather(key, value, -Theta) %>%
40 | ggplot() +
41 | geom_line(aes(x = Theta, y = value, color = key), alpha = .75) +
42 | labs(x = expression(theta), y = expression(I(theta)),
43 | title = title, subtitle = subtitle) +
44 | theme_minimal() +
45 | theme(legend.position = "bottom") +
46 | theme(legend.title=element_blank())
47 |
48 | return(p)
49 |
50 | }
51 |
--------------------------------------------------------------------------------
/R/testInfoPlot.r:
--------------------------------------------------------------------------------
1 | #' Plotting test information curve
2 | #'
3 | #' This function takes a fitted mirt-model and visualizes test information curve.
4 | #'
5 | #'
6 | #' @param model an object of class `SingleGroupClass` returned by the function `mirt()`.
7 | #' @param theta_range range to be shown on the x-axis
8 | #' @param adj_factor adjustment factor for properly overlaying information and standard error.
9 | #' @param title title for the plot (defaults to "Item Characteristic Curves")
10 | #'
11 | #' @return a ggplot
12 | #' @import ggplot2
13 | #' @import dplyr
14 | #' @import tidyr
15 | #' @import mirt
16 | #' @export
17 | #'
18 | #' @examples
19 | #' library(mirt)
20 | #' library(ggmirt)
21 | #' data <- expand.table(LSAT7)
22 | #' (mod <- mirt(data, 1))
23 | #'
24 | #' testInfoPlot(mod)
25 | #'
26 | testInfoPlot <- function(model,
27 | theta_range = c(-4,4),
28 | adj_factor = 3.5,
29 | title = "Test Information Curve") {
30 |
31 | theta_range = seq(theta_range[1], theta_range[2], by = .01)
32 |
33 | Theta <- matrix(theta_range)
34 | information <- testinfo(model, Theta)
35 | SE <- 1/(sqrt(information))
36 |
37 | p <- data.frame(Theta, information, SE) %>%
38 | mutate(SE = SE/adj_factor) %>%
39 | gather(key, value, -Theta) %>%
40 | ggplot() +
41 | geom_line(aes(x = Theta, y = value, color = key, linetype = key)) +
42 | scale_linetype_manual(values=c("solid", "dashed"))+
43 | scale_y_continuous(sec.axis = sec_axis(~.*adj_factor, name = expression(SE(theta)))) +
44 | labs(x = expression(theta), y = expression(I(theta)),
45 | title = title) +
46 | theme_minimal() +
47 | theme(legend.position = "bottom") +
48 | theme(legend.title=element_blank()) +
49 | scale_color_manual(values = c("red", "darkred"))
50 |
51 | return(p)
52 |
53 | }
54 |
--------------------------------------------------------------------------------
/R/tracePlot.r:
--------------------------------------------------------------------------------
1 | #' Plotting item characteristics curves
2 | #'
3 | #' This function takes a fitted mirt-model and the underlying data and visualizes item characteristic curves.
4 | #'
5 | #'
6 | #' @param model an object of class `SingleGroupClass` returned by the function `mirt()`.
7 | #' @param items numerical vector indicating which items to plot (currently does not yet work for graded response models).
8 | #' @param theta_range range to be shown on the x-axis
9 | #' @param n.answers In a graded response model, number of answer options (e.g., 5-point scale = 5)
10 | #' @param title title for the plot (defaults to "Item Characteristic Curves")
11 | #' @param facet Should all items be shown in one plot, or each item received its individual facet?
12 | #'
13 | #' @return a ggplot
14 | #' @import ggplot2
15 | #' @import dplyr
16 | #' @import tidyr
17 | #' @import mirt
18 | #' @export
19 | #'
20 | #' @examples
21 | #' library(mirt)
22 | #' library(ggmirt)
23 | #' data <- expand.table(LSAT7)
24 | #' (mod <- mirt(data, 1))
25 | #'
26 | #' tracePlot(mod)
27 | #' tracePlot(mod, items = c(1,2,3), theta_range = c(-5,5), facet = F, legend = T)
28 | #'
29 | tracePlot <- function(model,
30 | items = NULL,
31 | theta_range = c(-4,4),
32 | title = "Item Characteristics Curves",
33 | n.answers = 5,
34 | facet = TRUE,
35 | legend = FALSE) {
36 |
37 | data <- model@Data$data %>% as.data.frame
38 |
39 | # Set theta range as sequence
40 | theta_range = seq(theta_range[1], theta_range[2], by = .01)
41 |
42 | # Check model type
43 | type <- model@Model$itemtype
44 |
45 | # Graded response model
46 | if(type[1] == "graded") {
47 |
48 | trace <- probtrace(model, Theta = theta_range) %>%
49 | as_tibble %>%
50 | mutate(Theta = theta_range) %>%
51 | gather(key, value, -Theta) %>%
52 | separate(key, c("var", "response"), sep = ifelse(n.answers > 10, -4, -3))
53 |
54 | p <- ggplot(trace, aes(x = Theta, y = value)) +
55 | geom_line(aes(color = response)) +
56 | facet_wrap(~var) +
57 | theme_minimal() +
58 | labs(x = expression(theta),
59 | y = expression(P(theta)),
60 | title = title) +
61 | scale_color_brewer(palette = 7)
62 |
63 | } else {
64 |
65 | trace <- NULL
66 | for(i in 1:length(data)){
67 | extr <- extract.item(model, i)
68 | theta <- matrix(theta_range)
69 | trace[[i]] <- probtrace(extr, theta)
70 | }
71 |
72 | if (!is.null(items)) {
73 | trace <- trace[items]
74 | }
75 |
76 | names(trace) <- paste('item', 1:length(trace))
77 | trace_df <- do.call(rbind, trace)
78 |
79 | item <- rep(names(trace), each = length(theta))
80 | d <- cbind.data.frame(theta, item, trace_df)
81 | d$item <- as.factor(d$item)
82 |
83 | # final plot
84 | if(isFALSE(facet)) {
85 | p <- ggplot(d, aes(theta, P.1, colour = item)) +
86 | geom_line() +
87 | labs(x = expression(theta),
88 | y = expression(P(theta)),
89 | title = title) +
90 | theme_minimal() +
91 | scale_color_brewer(palette = 7)
92 |
93 | if(isFALSE(legend)) {
94 | p <- p + guides(color = "none")
95 | }
96 |
97 | } else {
98 | p <- ggplot(d, aes(theta, P.1)) +
99 | geom_line() +
100 | facet_wrap(~item) +
101 | labs(x = expression(theta),
102 | y = expression(P(theta)),
103 | title = title) +
104 | theme_minimal()
105 | }
106 |
107 | }
108 | return(p)
109 | }
110 |
--------------------------------------------------------------------------------
/R/utils-pipe.r:
--------------------------------------------------------------------------------
1 | #' Pipe operator
2 | #'
3 | #' See \code{magrittr::\link[magrittr:pipe]{\%>\%}} for details.
4 | #'
5 | #' @name %>%
6 | #' @rdname pipe
7 | #' @keywords internal
8 | #' @export
9 | #' @importFrom magrittr %>%
10 | #' @usage lhs \%>\% rhs
11 | NULL
12 |
--------------------------------------------------------------------------------
/README.md:
--------------------------------------------------------------------------------
1 |
2 |
3 |
4 |
5 |
6 |

7 |
8 |
9 |
10 | # ggmirt
11 |
12 |
13 |
14 | [](https://www.tidyverse.org/lifecycle/#experimental)
16 | [](https://CRAN.R-project.org/package=ggmirt)
18 |
19 |
20 | This package extends the great R-package
21 | [`mirt`](https://github.com/philchalmers/mirt) (Multidimensional item
22 | response theory; Chalmers, 2021) with functions for creating
23 | publication-ready and customizable figures. Although the `mirt`-packages
24 | already includes possibilities to plot various aspects relevant to
25 | understanding IRT analyses (e.g., item plots, trace-plots, etc.), it
26 | does not employ `ggplot2`, which provides more flexibility and
27 | customizability. This package provides some functions to recreate such
28 | plots with ggplot2.
29 |
30 | If you want to learn how to use `mirt` in combination with `ggmirt` to
31 | run various IRT analyses, please check out the following tutorials:
32 |
33 | - [Item Response Theory I: 3PL, 2PL, & 1PL (Rasch)
34 | models](https://github.com/ccs-amsterdam/r-course-material/blob/master/tutorials/R_test-theory_3_irt.md)
35 | - [Item Response Theory II: Graded response
36 | models](https://github.com/ccs-amsterdam/r-course-material/blob/master/tutorials/R_test-theory_3_irt_graded.md)
37 |
38 | **Please note:** This package is still under development. It is
39 | currently rather a place where I dump some functions that I use often,
40 | but I have not fully tested them under different scenarios and with
41 | different type of models. If you are interested in contributing, feel
42 | free to reach out.
43 |
44 | ### Installation
45 |
46 | ``` r
47 | # install.packages("devtools")
48 | devtools::install_github("masurp/ggmirt")
49 | ```
50 |
51 | ### Usage
52 |
53 | ``` r
54 | # Load packages
55 | library(mirt)
56 | library(ggmirt)
57 |
58 | # Simulate some data
59 | data <- sim_irt(500, 8, seed = 123)
60 |
61 | # Run IRT model with mirt
62 | mod <- mirt(data, 1, itemtype = "2PL", verbose = FALSE)
63 |
64 | # Plot item-person map
65 | itempersonMap(mod)
66 | ```
67 |
68 |
69 |
70 | ``` r
71 | # Item characteristic curves
72 | tracePlot(mod, data)
73 | ```
74 |
75 |
76 |
77 | ``` r
78 | # Item information curves
79 | itemInfoPlot(mod, data)
80 | ```
81 |
82 |
83 |
84 | ``` r
85 | # Scale characteristic curve
86 | scaleCharPlot(mod)
87 | ```
88 |
89 |
90 |
91 | ``` r
92 | # Test information curves
93 | testInfoPlot(mod, adj_factor = 1.75)
94 | ```
95 |
96 |
97 |
98 | ``` r
99 | # Item infit and outfit statistics
100 | itemfitPlot(mod)
101 | ```
102 |
103 |
104 |
105 | ``` r
106 | # Person fit statisitcs
107 | personfitPlot(mod)
108 | ```
109 |
110 |
111 |
112 | ``` r
113 | # Conditional reliability
114 | conRelPlot(mod)
115 | ```
116 |
117 |
118 |
119 | Next to individual plot functions, there is also a comprehensive
120 | summaryPlot()-function, which provides a lot of information about IRT
121 | models with just a line of code.
122 |
123 | ``` r
124 | summaryPlot(mod, adj_factor = 1.75)
125 | ```
126 |
127 |
128 |
129 | ### How to cite this package
130 |
131 | ``` r
132 | citation("ggmirt")
133 | #>
134 | #> To cite package 'ggmirt' in publications use:
135 | #>
136 | #> Philipp K. Masur (2022). ggmirt: Plotting functions to extend "mirt"
137 | #> for IRT analyses. R package version 0.1.0.
138 | #>
139 | #> A BibTeX entry for LaTeX users is
140 | #>
141 | #> @Manual{,
142 | #> title = {ggmirt: Plotting functions to extend "mirt" for IRT analyses},
143 | #> author = {Philipp K. Masur},
144 | #> year = {2022},
145 | #> note = {R package version 0.1.0},
146 | #> }
147 | ```
148 |
--------------------------------------------------------------------------------
/README.rmd:
--------------------------------------------------------------------------------
1 | ---
2 | output: github_document
3 | ---
4 |
5 |
6 |
7 | ```{r, include = FALSE}
8 | knitr::opts_chunk$set(
9 | collapse = TRUE,
10 | comment = "#>",
11 | fig.path = "man/figures/README-",
12 | out.width = "100%",
13 | fig.retina = 2
14 | )
15 | ```
16 |
17 |
18 |
19 |

20 |
21 |
22 |
23 |
24 | # ggmirt
25 |
26 |
27 | [](https://www.tidyverse.org/lifecycle/#experimental)
28 | [](https://CRAN.R-project.org/package=ggmirt)
29 |
30 |
31 | This package extends the great R-package [`mirt`](https://github.com/philchalmers/mirt) (Multidimensional item response theory; Chalmers, 2021) with functions for creating publication-ready and customizable figures. Although the `mirt`-packages already includes possibilities to plot various aspects relevant to understanding IRT analyses (e.g., item plots, trace-plots, etc.), it does not employ `ggplot2`, which provides more flexibility and customizability. This package provides some functions to recreate such plots with ggplot2.
32 |
33 | If you want to learn how to use `mirt` in combination with `ggmirt` to run various IRT analyses, please check out the following tutorials:
34 |
35 | - [Item Response Theory I: 3PL, 2PL, & 1PL (Rasch) models](https://github.com/ccs-amsterdam/r-course-material/blob/master/tutorials/R_test-theory_3_irt.md)
36 | - [Item Response Theory II: Graded response models](https://github.com/ccs-amsterdam/r-course-material/blob/master/tutorials/R_test-theory_3_irt_graded.md)
37 |
38 |
39 | **Please note:** This package is still under development. It is currently rather a place where I dump some functions that I use often, but I have not fully tested them under different scenarios and with different type of models. If you are interested in contributing, feel free to reach out.
40 |
41 |
42 | ### Installation
43 |
44 | ``` r
45 | # install.packages("devtools")
46 | devtools::install_github("masurp/ggmirt")
47 | ```
48 |
49 |
50 | ### Usage
51 |
52 | ```{r, message=F, warning = F, fig.width=7, fig.height=8.5}
53 | # Load packages
54 | library(mirt)
55 | library(ggmirt)
56 |
57 | # Simulate some data
58 | data <- sim_irt(500, 8, seed = 123)
59 |
60 | # Run IRT model with mirt
61 | mod <- mirt(data, 1, itemtype = "2PL", verbose = FALSE)
62 |
63 | # Plot item-person map
64 | itempersonMap(mod)
65 | ```
66 |
67 |
68 | ```{r, message=F, warning = F}
69 | # Item characteristic curves
70 | tracePlot(mod)
71 | ```
72 |
73 |
74 | ```{r, message=F, warning = F}
75 | # Item information curves
76 | itemInfoPlot(mod)
77 | ```
78 |
79 |
80 | ```{r, message=F, warning = F}
81 | # Scale characteristic curve
82 | scaleCharPlot(mod)
83 | ```
84 |
85 |
86 | ```{r, message=F, warning = F}
87 | # Test information curves
88 | testInfoPlot(mod, adj_factor = 1.75)
89 | ```
90 |
91 |
92 | ```{r, message=F, warning = F}
93 | # Item infit and outfit statistics
94 | itemfitPlot(mod)
95 | ```
96 |
97 |
98 | ```{r, message=F, warning = F}
99 | # Person fit statisitcs
100 | personfitPlot(mod)
101 | ```
102 |
103 |
104 | ```{r, message=F, warning = F}
105 | # Conditional reliability
106 | conRelPlot(mod)
107 | ```
108 |
109 |
110 | Next to individual plot functions, there is also a comprehensive summaryPlot()-function, which provides a lot of information about IRT models with just a line of code.
111 |
112 | ```{r, message=F, warning = F, fig.width=8, fig.height=8}
113 | summaryPlot(mod, adj_factor = 1.75)
114 | ```
115 |
116 |
117 |
118 |
119 | ### How to cite this package
120 |
121 | ```{r, message=F, warning = F}
122 | citation("ggmirt")
123 | ```
124 |
125 |
126 |
--------------------------------------------------------------------------------
/ggmirt.Rproj:
--------------------------------------------------------------------------------
1 | Version: 1.0
2 |
3 | RestoreWorkspace: Default
4 | SaveWorkspace: Default
5 | AlwaysSaveHistory: Default
6 |
7 | EnableCodeIndexing: Yes
8 | UseSpacesForTab: Yes
9 | NumSpacesForTab: 2
10 | Encoding: UTF-8
11 |
12 | RnwWeave: Sweave
13 | LaTeX: pdfLaTeX
14 |
15 | BuildType: Package
16 | PackageUseDevtools: Yes
17 | PackageInstallArgs: --no-multiarch --with-keep.source
18 | PackageRoxygenize: rd,collate,namespace
19 |
--------------------------------------------------------------------------------
/inst/figures/logo.png:
--------------------------------------------------------------------------------
https://raw.githubusercontent.com/masurp/ggmirt/4cfa1069f12409e0d8420ec67468a7f32351d0b3/inst/figures/logo.png
--------------------------------------------------------------------------------
/man/conRelPlot.Rd:
--------------------------------------------------------------------------------
1 | % Generated by roxygen2: do not edit by hand
2 | % Please edit documentation in R/conRelPlot.r
3 | \name{conRelPlot}
4 | \alias{conRelPlot}
5 | \title{Plotting conditional reliability}
6 | \usage{
7 | conRelPlot(
8 | model,
9 | theta_range = c(-4, 4),
10 | color = "red",
11 | title = "Conditional Reliability"
12 | )
13 | }
14 | \arguments{
15 | \item{model}{an object of class \code{SingleGroupClass} returned by the function \code{mirt()}.}
16 |
17 | \item{theta_range}{range to be shown on the x-axis}
18 |
19 | \item{color}{color of the line}
20 |
21 | \item{title}{title for the plot (defaults to "Conditional Reliability")}
22 | }
23 | \value{
24 | a ggplot
25 | }
26 | \description{
27 | This function takes a fitted mirt-model and visualizes a conditional reliability curve. Heavily inspired by code from Phil Chalmers (author or 'mirt')
28 | }
29 | \examples{
30 | library(mirt)
31 | library(ggmirt)
32 | data <- expand.table(LSAT7)
33 | (mod <- mirt(data, 1))
34 |
35 | conRelPlot(mod)
36 | }
37 |
--------------------------------------------------------------------------------
/man/figures/README-unnamed-chunk-10-1.png:
--------------------------------------------------------------------------------
https://raw.githubusercontent.com/masurp/ggmirt/4cfa1069f12409e0d8420ec67468a7f32351d0b3/man/figures/README-unnamed-chunk-10-1.png
--------------------------------------------------------------------------------
/man/figures/README-unnamed-chunk-2-1.png:
--------------------------------------------------------------------------------
https://raw.githubusercontent.com/masurp/ggmirt/4cfa1069f12409e0d8420ec67468a7f32351d0b3/man/figures/README-unnamed-chunk-2-1.png
--------------------------------------------------------------------------------
/man/figures/README-unnamed-chunk-2-2.png:
--------------------------------------------------------------------------------
https://raw.githubusercontent.com/masurp/ggmirt/4cfa1069f12409e0d8420ec67468a7f32351d0b3/man/figures/README-unnamed-chunk-2-2.png
--------------------------------------------------------------------------------
/man/figures/README-unnamed-chunk-3-1.png:
--------------------------------------------------------------------------------
https://raw.githubusercontent.com/masurp/ggmirt/4cfa1069f12409e0d8420ec67468a7f32351d0b3/man/figures/README-unnamed-chunk-3-1.png
--------------------------------------------------------------------------------
/man/figures/README-unnamed-chunk-4-1.png:
--------------------------------------------------------------------------------
https://raw.githubusercontent.com/masurp/ggmirt/4cfa1069f12409e0d8420ec67468a7f32351d0b3/man/figures/README-unnamed-chunk-4-1.png
--------------------------------------------------------------------------------
/man/figures/README-unnamed-chunk-5-1.png:
--------------------------------------------------------------------------------
https://raw.githubusercontent.com/masurp/ggmirt/4cfa1069f12409e0d8420ec67468a7f32351d0b3/man/figures/README-unnamed-chunk-5-1.png
--------------------------------------------------------------------------------
/man/figures/README-unnamed-chunk-6-1.png:
--------------------------------------------------------------------------------
https://raw.githubusercontent.com/masurp/ggmirt/4cfa1069f12409e0d8420ec67468a7f32351d0b3/man/figures/README-unnamed-chunk-6-1.png
--------------------------------------------------------------------------------
/man/figures/README-unnamed-chunk-7-1.png:
--------------------------------------------------------------------------------
https://raw.githubusercontent.com/masurp/ggmirt/4cfa1069f12409e0d8420ec67468a7f32351d0b3/man/figures/README-unnamed-chunk-7-1.png
--------------------------------------------------------------------------------
/man/figures/README-unnamed-chunk-8-1.png:
--------------------------------------------------------------------------------
https://raw.githubusercontent.com/masurp/ggmirt/4cfa1069f12409e0d8420ec67468a7f32351d0b3/man/figures/README-unnamed-chunk-8-1.png
--------------------------------------------------------------------------------
/man/figures/README-unnamed-chunk-9-1.png:
--------------------------------------------------------------------------------
https://raw.githubusercontent.com/masurp/ggmirt/4cfa1069f12409e0d8420ec67468a7f32351d0b3/man/figures/README-unnamed-chunk-9-1.png
--------------------------------------------------------------------------------
/man/itemDist.Rd:
--------------------------------------------------------------------------------
1 | % Generated by roxygen2: do not edit by hand
2 | % Please edit documentation in R/itemDistribution.r
3 | \name{itemDist}
4 | \alias{itemDist}
5 | \title{Item difficulty distribution}
6 | \usage{
7 | itemDist(model, theta_range = c(-4, 4), ...)
8 | }
9 | \arguments{
10 | \item{model}{an object of class \code{SingleGroupClass} returned by the function \code{mirt()}.}
11 |
12 | \item{...}{any argument passed to \code{geom_point()}}
13 | }
14 | \value{
15 | a ggplot object.
16 | }
17 | \description{
18 | This function requires a fitted mirt-model of class \code{SingleGroupClass} to visualize item difficulty distribution. Currently only works for unidimensional models.
19 | }
20 | \examples{
21 | # Loading packages
22 | library(mirt)
23 | library(ggmirt)
24 |
25 | # Getting data
26 | data <- expand.table(LSAT7)
27 |
28 | # Fitting a model
29 | (mod <- mirt(data, 1))
30 |
31 | # Simple plot
32 | itemDist(mod)
33 |
34 | # Customized plot
35 | itemDist(mod, size = 3, shape = 17, color = "blue")
36 |
37 | }
38 |
--------------------------------------------------------------------------------
/man/itemInfoPlot.Rd:
--------------------------------------------------------------------------------
1 | % Generated by roxygen2: do not edit by hand
2 | % Please edit documentation in R/itemInfoPlot.r
3 | \name{itemInfoPlot}
4 | \alias{itemInfoPlot}
5 | \title{Plotting item information curves}
6 | \usage{
7 | itemInfoPlot(
8 | model,
9 | items = NULL,
10 | facet = FALSE,
11 | title = "Item Information Curves",
12 | theta_range = c(-4, 4),
13 | legend = FALSE
14 | )
15 | }
16 | \arguments{
17 | \item{model}{an object of class \code{SingleGroupClass} returned by the function \code{mirt()}.}
18 |
19 | \item{items}{numerical vector indicating which items to plot.}
20 |
21 | \item{facet}{Should all items be shown in one plot, or each item received its individal facet?}
22 |
23 | \item{title}{title for the plot (defaults to "Item Characteristic Curves")}
24 |
25 | \item{theta_range}{range to be shown on the x-axis}
26 | }
27 | \value{
28 | a ggplot
29 | }
30 | \description{
31 | This function takes a fitted mirt-model and visualizes items information curves.
32 | }
33 | \examples{
34 | library(mirt)
35 | library(ggmirt)
36 | data <- expand.table(LSAT7)
37 | (mod <- mirt(data, 1))
38 |
39 | itemInfoPlot(mod)
40 |
41 | }
42 |
--------------------------------------------------------------------------------
/man/itemfitPlot.Rd:
--------------------------------------------------------------------------------
1 | % Generated by roxygen2: do not edit by hand
2 | % Please edit documentation in R/itemfitPlot.r
3 | \name{itemfitPlot}
4 | \alias{itemfitPlot}
5 | \title{Plotting itemfit estimates}
6 | \usage{
7 | itemfitPlot(
8 | model,
9 | fit_stats = "infit",
10 | color = "red",
11 | shape = 17,
12 | title = "Item Infit and Outfit Statistics",
13 | ...
14 | )
15 | }
16 | \arguments{
17 | \item{model}{an object of class \code{SingleGroupClass} returned by the function \code{mirt()}.}
18 |
19 | \item{fit_stats}{a character vector indicating which fit statistics should be computed. See \code{mirt::infit()} for supported inputs.}
20 |
21 | \item{color}{color of the item points.}
22 |
23 | \item{shape}{shape of the item points}
24 |
25 | \item{title}{title for the plot (defaults to "Item Infit and Outfit Statistics")}
26 | }
27 | \value{
28 | a ggplot
29 | }
30 | \description{
31 | This function takes a fitted mirt-model and visualizes item infit and outfit estimates. The function builds on \code{mirt::itemfit()}. Currently only supported \code{fact_stats = "infit"}.
32 | }
33 | \examples{
34 | library(mirt)
35 | library(ggmirt)
36 | data <- expand.table(LSAT7)
37 | (mod <- mirt(data, 1))
38 |
39 | itemfitPlot(mod, fit_stats = "infit")
40 |
41 | }
42 | \references{
43 | \itemize{
44 | \item Linacre JM. (2002). What do Infit and Outfit, Mean-square and Standardized mean? Rasch Measurement Transactions, 16(2), p.878. https://www.rasch.org/rmt/rmt162f.htm
45 | }
46 | }
47 |
--------------------------------------------------------------------------------
/man/itempersonMap.Rd:
--------------------------------------------------------------------------------
1 | % Generated by roxygen2: do not edit by hand
2 | % Please edit documentation in R/itempersonMap.r
3 | \name{itempersonMap}
4 | \alias{itempersonMap}
5 | \title{Visualize item person map and scale properties based on Rasch model}
6 | \usage{
7 | itempersonMap(
8 | model,
9 | theta_range = c(-4, 4),
10 | title = "Item Person Map",
11 | margin = c(1, 0, -1.5, 0),
12 | density = FALSE,
13 | color = "red",
14 | shape = 17,
15 | size = 3,
16 | theme = theme_minimal(),
17 | ...
18 | )
19 | }
20 | \arguments{
21 | \item{model}{an object of class \code{SingleGroupClass} returned by the function \code{mirt()}.}
22 |
23 | \item{title}{title for the plot (defaults to "Item-Person-Map")}
24 |
25 | \item{margin}{margins around the top figure. Sometimes one might want to adjust this.}
26 |
27 | \item{density}{logical value indicating whether a smoothed density curve or a standard histogram should be plotted.}
28 |
29 | \item{color}{color of the geoms, defaults to "red".}
30 |
31 | \item{shape}{can be used to change the shape of the geom, defaults to triangles (17).}
32 |
33 | \item{size}{size of the geom, default to 3.}
34 |
35 | \item{theme}{any ggplot theme.}
36 |
37 | \item{...}{any argument passed to \code{geom_point()}.}
38 |
39 | \item{limits}{range to be shown on the x-axis}
40 | }
41 | \value{
42 | a plot grid as returned by \code{cowplot::plot_grid()}
43 | }
44 | \description{
45 | This function takes a fitted mirt-model and visualizes and plots item-person-map (also known as Kernel-Density Plots or Wright maps) on the left, and add a scale characteristic curve, scale information curve, and a marginal reliability curve on the right.
46 | }
47 | \examples{
48 | library(mirt)
49 | library(ggmirt)
50 | data <- expand.table(LSAT7)
51 | (mod <- mirt(data, 1))
52 |
53 | itempersonMap(mod)
54 |
55 | }
56 |
--------------------------------------------------------------------------------
/man/personDist.Rd:
--------------------------------------------------------------------------------
1 | % Generated by roxygen2: do not edit by hand
2 | % Please edit documentation in R/personDistribution.r
3 | \name{personDist}
4 | \alias{personDist}
5 | \title{Person parameter distribution}
6 | \usage{
7 | personDist(model, theta_range = c(-4, 4), density = FALSE, bins = 35)
8 | }
9 | \arguments{
10 | \item{model}{an object of class \code{SingleGroupClass} returned by the function \code{mirt()}.}
11 |
12 | \item{density}{logical value indicating whether a smoothed density curve or a standard histogram should be plotted.}
13 |
14 | \item{bins}{number of bins to be plotted in the histogram}
15 | }
16 | \value{
17 | a ggplot object.
18 | }
19 | \description{
20 | This function requires a fitted mirt-model of class \code{SingleGroupClass} to visualize a person parameter distribution (theta levels in the studied population). The resulting ggplot can be further customized (e.g., with regard to theme, labels, etc.). It works with both uni- and multidimensional models.
21 | }
22 | \examples{
23 | # Loading packages
24 | library(mirt)
25 | library(ggmirt)
26 |
27 | # Getting data
28 | data <- expand.table(LSAT7)
29 |
30 | # Fitting a model
31 | (mod <- mirt(data, 1))
32 |
33 | # Simple plot
34 | personDist(mod)
35 | personDist(mod, density = TRUE)
36 |
37 | # Customized plot
38 | personDist(mod, theta_range = c(-3, 3), bins = 10) +
39 | theme_classic()
40 | }
41 |
--------------------------------------------------------------------------------
/man/personfitPlot.Rd:
--------------------------------------------------------------------------------
1 | % Generated by roxygen2: do not edit by hand
2 | % Please edit documentation in R/personfitPlot.r
3 | \name{personfitPlot}
4 | \alias{personfitPlot}
5 | \title{Plotting personfit estimates}
6 | \usage{
7 | personfitPlot(model, std = TRUE, title = "Person Infit and Outfit Statistics")
8 | }
9 | \arguments{
10 | \item{model}{an object of class \code{SingleGroupClass} returned by the function \code{mirt()}.}
11 |
12 | \item{std}{logical value indicating whether standardized or non-standardized infit or outfit estimates should be used (leads to different cut-off values).}
13 |
14 | \item{title}{title for the plot (defaults to "Person Infit and Outfit Statistics")}
15 | }
16 | \value{
17 | a ggplot
18 | }
19 | \description{
20 | This function takes a fitted mirt-model and visualizes person infit and outfit estimates. The function builds on \code{mirt::itemfit()}. The basic idea is to visualize how many individuals in the sample do not show a response pattern that aligns with the suggested model. At best, the number of non-fitting response patterns is low (e.g., < 5\%).
21 | }
22 | \examples{
23 | library(mirt)
24 | library(ggmirt)
25 | data <- expand.table(LSAT7)
26 | (mod <- mirt(data, 1))
27 |
28 | personfitPlot(mod, std = F)
29 |
30 | }
31 | \references{
32 | \itemize{
33 | \item Linacre JM. (2002). What do Infit and Outfit, Mean-square and Standardized mean? Rasch Measurement Transactions, 16(2), p.878. https://www.rasch.org/rmt/rmt162f.htm
34 | }
35 | }
36 |
--------------------------------------------------------------------------------
/man/pipe.Rd:
--------------------------------------------------------------------------------
1 | % Generated by roxygen2: do not edit by hand
2 | % Please edit documentation in R/utils-pipe.r
3 | \name{\%>\%}
4 | \alias{\%>\%}
5 | \title{Pipe operator}
6 | \usage{
7 | lhs \%>\% rhs
8 | }
9 | \description{
10 | See \code{magrittr::\link[magrittr:pipe]{\%>\%}} for details.
11 | }
12 | \keyword{internal}
13 |
--------------------------------------------------------------------------------
/man/scaleCharPlot.Rd:
--------------------------------------------------------------------------------
1 | % Generated by roxygen2: do not edit by hand
2 | % Please edit documentation in R/scaleCharPlot.r
3 | \name{scaleCharPlot}
4 | \alias{scaleCharPlot}
5 | \title{Scale Characteristic Curve}
6 | \usage{
7 | scaleCharPlot(
8 | model,
9 | theta_range = c(-4, 4),
10 | color = "red",
11 | title = "Scale Characteristic Curve"
12 | )
13 | }
14 | \arguments{
15 | \item{model}{an object of class \code{SingleGroupClass} returned by the function \code{mirt()}.}
16 |
17 | \item{theta_range}{range to be shown on the x-axis}
18 |
19 | \item{color}{color of the line}
20 |
21 | \item{title}{title for the plot (defaults to "Person Infit and Outfit Statistics")}
22 | }
23 | \value{
24 | a ggplot
25 | }
26 | \description{
27 | Once model-based theta score estimates are computed, it often is of interest to transform those estimates into the original scale metric. A scale characteristic function provides a means of transforming estimated theta scores to expected true scores in the original scale metric. This transformation back into the original scale metric provides a more familiar frame of reference for interpreting scores. This function provides a visualization for this transformation.
28 | }
29 | \examples{
30 | library(mirt)
31 | library(ggmirt)
32 | data <- expand.table(LSAT7)
33 | (mod <- mirt(data, 1))
34 |
35 | scaleCharPlot(mod)
36 |
37 | }
38 |
--------------------------------------------------------------------------------
/man/sim_irt.Rd:
--------------------------------------------------------------------------------
1 | % Generated by roxygen2: do not edit by hand
2 | % Please edit documentation in R/sim_irt.r
3 | \name{sim_irt}
4 | \alias{sim_irt}
5 | \title{Helper function to simulate IRT data}
6 | \usage{
7 | sim_irt(
8 | n.obs = 100,
9 | n.items = 10,
10 | discrimination = 0,
11 | seed = NULL,
12 | cut = "random"
13 | )
14 | }
15 | \arguments{
16 | \item{n.obs}{Number of observations that should be included in the data set}
17 |
18 | \item{n.items}{Number of items that should be simulated}
19 |
20 | \item{discrimination}{Standard deviation on the log scale}
21 |
22 | \item{seed}{Seed for the random number generation process}
23 |
24 | \item{cut}{Either "random" for a randomized transformation of the model probability matrix into the model 0-1 matrix or an integer value between 0 and 1.}
25 | }
26 | \value{
27 | a tibble
28 | }
29 | \description{
30 | Function to simulate data that can be used to fit IRT models.
31 | }
32 | \examples{
33 | library(ggmirt)
34 |
35 | sim_irt(n.obs = 200, n.items = 10)
36 |
37 | }
38 |
--------------------------------------------------------------------------------
/man/summaryPlot.Rd:
--------------------------------------------------------------------------------
1 | % Generated by roxygen2: do not edit by hand
2 | % Please edit documentation in R/summaryPlot.r
3 | \name{summaryPlot}
4 | \alias{summaryPlot}
5 | \title{A quick summary of IRT analyses}
6 | \usage{
7 | summaryPlot(model, theta_range = c(-4, 4), adj_factor = 0.05)
8 | }
9 | \arguments{
10 | \item{model}{an object of class \code{SingleGroupClass} returned by the function \code{mirt()}.}
11 |
12 | \item{theta_range}{range to be shown on the x-axis}
13 |
14 | \item{adj_factor}{adjustment factor for properly overlaying information and standard error.}
15 | }
16 | \value{
17 | a plot grid as returned by \code{cowplot::ggdraw()}
18 | }
19 | \description{
20 | This function is essentially just a wrapper around several functions in this package and produces a summary of the most important aspects of an IRT model, including an item-person-map,test information curve, scale characteristic curve, and conditional reliability.
21 | }
22 | \examples{
23 | library(mirt)
24 | library(ggmirt)
25 |
26 | # Simulate some data
27 | data <- sim_irt(500, 10, seed = 123)
28 |
29 | # Run IRT model with mirt
30 | mod <- mirt(data, 1, itemtype = "2PL", verbose = FALSE)
31 |
32 | summaryPlot(mod, theta_range = c(-4.5, 3.5), adj_factor = 1.5)
33 |
34 | }
35 |
--------------------------------------------------------------------------------
/man/testInfoCompare.Rd:
--------------------------------------------------------------------------------
1 | % Generated by roxygen2: do not edit by hand
2 | % Please edit documentation in R/testInfoCompare.r
3 | \name{testInfoCompare}
4 | \alias{testInfoCompare}
5 | \title{Comparing test information curves of parallel tests}
6 | \usage{
7 | testInfoCompare(
8 | model1,
9 | model2,
10 | theta_range = c(-4, 4),
11 | title = "Parallel Tests",
12 | subtitle = "Test Information Curves"
13 | )
14 | }
15 | \arguments{
16 | \item{model1}{an object of class \code{SingleGroupClass} returned by the function \code{mirt()}.}
17 |
18 | \item{model2}{an object of class \code{SingleGroupClass}}
19 |
20 | \item{title}{title for the plot}
21 |
22 | \item{subtitle}{subtitle for the plot}
23 | }
24 | \value{
25 | a ggplot
26 | }
27 | \description{
28 | This function takes two fitted mirt-model and visualizes test their test information curves on top of each other. This can be helpful for finding parallel tests.
29 | }
30 | \examples{
31 | library(mirt)
32 | library(ggmirt)
33 | data <- expand.table(LSAT7)
34 | (mod1 <- mirt(data, 1))
35 | (mod2 <- mirt(data[,1:4], 1))
36 |
37 | testInfoCompare(mod1, mod2)
38 |
39 | }
40 |
--------------------------------------------------------------------------------
/man/testInfoPlot.Rd:
--------------------------------------------------------------------------------
1 | % Generated by roxygen2: do not edit by hand
2 | % Please edit documentation in R/testInfoPlot.r
3 | \name{testInfoPlot}
4 | \alias{testInfoPlot}
5 | \title{Plotting test information curve}
6 | \usage{
7 | testInfoPlot(
8 | model,
9 | theta_range = c(-4, 4),
10 | adj_factor = 3.5,
11 | title = "Test Information Curve"
12 | )
13 | }
14 | \arguments{
15 | \item{model}{an object of class \code{SingleGroupClass} returned by the function \code{mirt()}.}
16 |
17 | \item{theta_range}{range to be shown on the x-axis}
18 |
19 | \item{adj_factor}{adjustment factor for properly overlaying information and standard error.}
20 |
21 | \item{title}{title for the plot (defaults to "Item Characteristic Curves")}
22 | }
23 | \value{
24 | a ggplot
25 | }
26 | \description{
27 | This function takes a fitted mirt-model and visualizes test information curve.
28 | }
29 | \examples{
30 | library(mirt)
31 | library(ggmirt)
32 | data <- expand.table(LSAT7)
33 | (mod <- mirt(data, 1))
34 |
35 | testInfoPlot(mod)
36 |
37 | }
38 |
--------------------------------------------------------------------------------
/man/tracePlot.Rd:
--------------------------------------------------------------------------------
1 | % Generated by roxygen2: do not edit by hand
2 | % Please edit documentation in R/tracePlot.r
3 | \name{tracePlot}
4 | \alias{tracePlot}
5 | \title{Plotting item characteristics curves}
6 | \usage{
7 | tracePlot(
8 | model,
9 | items = NULL,
10 | theta_range = c(-4, 4),
11 | title = "Item Characteristics Curves",
12 | n.answers = 5,
13 | facet = TRUE,
14 | legend = FALSE
15 | )
16 | }
17 | \arguments{
18 | \item{model}{an object of class \code{SingleGroupClass} returned by the function \code{mirt()}.}
19 |
20 | \item{items}{numerical vector indicating which items to plot (currently does not yet work for graded response models).}
21 |
22 | \item{theta_range}{range to be shown on the x-axis}
23 |
24 | \item{title}{title for the plot (defaults to "Item Characteristic Curves")}
25 |
26 | \item{n.answers}{In a graded response model, number of answer options (e.g., 5-point scale = 5)}
27 |
28 | \item{facet}{Should all items be shown in one plot, or each item received its individual facet?}
29 | }
30 | \value{
31 | a ggplot
32 | }
33 | \description{
34 | This function takes a fitted mirt-model and the underlying data and visualizes item characteristic curves.
35 | }
36 | \examples{
37 | library(mirt)
38 | library(ggmirt)
39 | data <- expand.table(LSAT7)
40 | (mod <- mirt(data, 1))
41 |
42 | tracePlot(mod)
43 | tracePlot(mod, items = c(1,2,3), theta_range = c(-5,5), facet = F, legend = T)
44 |
45 | }
46 |
--------------------------------------------------------------------------------