Multidimensional Item Response Theory

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Documentation for package ‘mirt’ version 1.42

• DESCRIPTION file.
• User guides, package vignettes and other documentation.
• Package NEWS.

Help Pages

mirt-package	Full information maximum likelihood estimation of IRT models.
anova-method	Compare nested models with likelihood-based statistics
areainfo	Function to calculate the area under a selection of information curves
ASVAB	Description of ASVAB data
averageMI	Collapse values from multiple imputation draws
bfactor	Full-Information Item Bi-factor and Two-Tier Analysis
Bock1997	Description of Bock 1997 data
boot.LR	Parametric bootstrap likelihood-ratio test
boot.mirt	Calculate bootstrapped standard errors for estimated models
coef-method	Extract raw coefs from model object
createGroup	Create a user defined group-level object with correct generic functions
createItem	Create a user defined item with correct generic functions
deAyala	Description of deAyala data
DIF	Differential item functioning statistics
DiscreteClass-class	Class "DiscreteClass"
draw_parameters	Draw plausible parameter instantiations from a given model
DRF	Differential Response Functioning statistics
DTF	Differential test functioning statistics
empirical_ES	Empirical effect sizes based on latent trait estimates
empirical_plot	Function to generate empirical unidimensional item and test plots
empirical_rxx	Function to calculate the empirical (marginal) reliability
estfun.AllModelClass	Extract Empirical Estimating Functions
expand.table	Expand summary table of patterns and frequencies
expected.item	Function to calculate expected value of item
expected.test	Function to calculate expected test score
extract.group	Extract a group from a multiple group mirt object
extract.item	Extract an item object from mirt objects
extract.mirt	Extract various elements from estimated model objects
fixedCalib	Fixed-item calibration method
fixef	Compute latent regression fixed effect expected values
fscores	Compute factor score estimates (a.k.a, ability estimates, latent trait estimates, etc)
gen.difficulty	Generalized item difficulty summaries
imputeMissing	Imputing plausible data for missing values
itemfit	Item fit statistics
itemGAM	Parametric smoothed regression lines for item response probability functions
iteminfo	Function to calculate item information
itemplot	Displays item surface and information plots
itemstats	Generic item summary statistics
key2binary	Score a test by converting response patterns to binary data
lagrange	Lagrange test for freeing parameters
likert2int	Convert ordered Likert-scale responses (character or factors) to integers
logLik-method	Extract log-likelihood
LSAT6	Description of LSAT6 data
LSAT7	Description of LSAT7 data
M2	Compute the M2 model fit statistic
marginal_rxx	Function to calculate the marginal reliability
MDIFF	Compute multidimensional difficulty index
mdirt	Multidimensional discrete item response theory
MDISC	Compute multidimensional discrimination index
mirt	Full-Information Item Factor Analysis (Multidimensional Item Response Theory)
mirt.model	Specify model information
mirtCluster	Define a parallel cluster object to be used in internal functions
MixedClass-class	Class "MixedClass"
mixedmirt	Mixed effects modeling for MIRT models
MixtureClass-class	Class "MixtureClass"
mod2values	Convert an estimated mirt model to a data.frame
multipleGroup	Multiple Group Estimation
MultipleGroupClass-class	Class "MultipleGroupClass"
numerical_deriv	Compute numerical derivatives
personfit	Person fit statistics
PLCI.mirt	Compute profiled-likelihood (or posterior) confidence intervals
plot-method	Plot various test-implied functions from models
plot.itemGAM	Parametric smoothed regression lines for item response probability functions
poly2dich	Change polytomous items to dichotomous item format
print-method	Print the model objects
print.mirt_df	Print generic for customized data.frame console output
print.mirt_list	Print generic for customized list console output
print.mirt_matrix	Print generic for customized matrix console output
probtrace	Function to calculate probability trace lines
randef	Compute posterior estimates of random effect
RCI	Model-based Reliable Change Index
read.mirt	Translate mirt parameters into suitable structure for plink package
remap.distance	Remap item categories to have integer distances of 1
residuals-method	Compute model residuals
reverse.score	Reverse score one or more items from a response matrix
RMSD_DIF	RMSD effect size statistic to quantify category-level DIF
SAT12	Description of SAT12 data
Science	Description of Science data
secondOrderTest	Second-order test of convergence
show-method	Show model object
SIBTEST	(Generalized) Simultaneous Item Bias Test (SIBTEST)
simdata	Simulate response patterns
SingleGroupClass-class	Class "SingleGroupClass"
SLF	Social Life Feelings Data
summary-method	Summary of model object
testinfo	Function to calculate test information
thetaComb	Create all possible combinations of vector input
traditional2mirt	Convert traditional IRT metric into slope-intercept form used in mirt
vcov-method	Extract parameter variance covariance matrix
wald	Wald statistics for mirt models