----------------------- sirt NEWS -----------------------------

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sirt: Supplementary Item Response Theory

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Alexander Robitzsch
Federal Institute for Educational Research, Innovation and 
Development of the Austrian School System (BIFIE)
Salzburg (Austria)
http://www.bifie.at

See also URL: 
https://sites.google.com/site/alexanderrobitzsch/software

Questions or suggestions about sirt can be sent to:
a.robitzsch /-\ bifie.at

For reporting a bug, please provide always a reproducible R script 
and (if necessary) a corresponding dataset.

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~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
CHANGELOG sirt
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~


------------------------------------------------------------------------
Versions 1.4/1.5 -- 2015-03-03  --  CRAN sirt 1.5-0
------------------------------------------------------------------------

NOTE  * changed default for argument 'itemcodes' in R2conquest fuction
NOTE  * included S3 methods for probabilistic Guttman model 'prob.guttman'
ADDED * included plot method for hierarchical rater model 'rm.sdt'
NOTE  * changed calculation of transformed parameters in 'rm.sdt'
FIXED * fixed a bug in 'rm.sdt' for datasets with differing number of
        item categories
ADDED * added option for specifying a discrete latemt variable in
        'rm.sdt' function. Options for fixed item parameters were also
        added.
NOTE  * added arguments for bounds of item slope and item difficulty
        parameters in 'rasch.mml2' (requested by Aysenur Erdemir)
ADDED * added option for estimating the missingness delta parameter
        in 'rasch.mml2' and 'irtmodel="missing1"'
FIXED * fixed a bug in 'rasch.mml2' for missing data models and 
        included CALL in summary
FIXED * corrected missing output of individual likelihood and posterior
        in 'rasch.mml2' for irtmodel='missing1'

DATA  * included/modified datasets: data.bs07a
EXAMP * included/modified examples: data.eid (4.3a),
        data.read (8e,9a), data.bs (07a), rm.sdt (2,3), rasch.mml2 (1,7)

------------------------------------------------------------------------
Versions 1.3 -- 2015-01-06  --  CRAN sirt 1.3
------------------------------------------------------------------------

NOTE  * defined several S3 methods for 'rasch.copula2' and 
        'rasch.copula3'
NOTE  * adapted S3 methods for mirt because the new class
        'SingleGroupClass' is defined in mirt >= 1.7 and removed
        'ConfirmatoryClass' and 'ExploratoryClass' methods
NOTE  * exported the object pcm.fit (it was spuriously 
        non-exported in sirt 1.2; reported by Sven Liepertz)
NOTE  * included the argument 'ignore.pid' for ignoring person
        identifiers in 'R2conquest' function (suggested by
        Kelvin Gregory)
NOTE  * changed Example 1 in 'f1d.irt' due to a change in 
        Suggests regarding the MASS package in the psych package
        which caused an error in CRAN checks (suggested by William 
        Revelle) 
ADDED * included S3 methods logLik, IRT.likelihood, IRT.posterior,
        IRT.modelfit, summary.IRT.modelfit and IRT.irfprob for 
        functions 'rasch.mml2', 'smirt', 'rasch.mirtlc', 'gom',
        'rm.facets' and 'rm.sdt'
NOTE  * extended modelfit.sirt for objects of class gom
ADDED * included function 'modelfit.cor.poly' for assessing
        absolute model fit for polytomous item responses
ADDED * included arguments for fixing item and rater parameters in 
        'rm.facets'
ADDED * included IRT.factor.scores method for 'rm.facets' and
        'rm.sdt'
ADDED * included function 'IRT.mle' for estimating MLE, WLE and
        MAP factor scores with user defined item response functions
        
DATA  * included/modified datasets: ---
EXAMP * included/modified examples: f1d.irt (1), rasch.mml2 (1),
        rasch.mirtlc (1), gom.em (1), rm.facets (2), IRT.mle (1,2,3)        

------------------------------------------------------------------------
Versions 1.2 -- 2014-12-12  --  CRAN sirt 1.2
------------------------------------------------------------------------

NOTE  * included standard errors of WLE parameters in 'wle.rasch'
NOTE  * corrected formulas help file for 'pcm.conversion'
        (thanks to Thomas Kiefer)
FIXED * fixed computational problems for calculating tetrachoric        
        correlation with empty cells in 'tetrachoric2' resp.
        'polychoric2' (method of Olsson; thanks to a dataset 
        privided by Ulrike Kipman)
NOTE  * included S3 methods IRT.likelihood, IRT.posterior and
        IRT.irfprob for two classes (ConfirmatoryClass and
        ExploratoryClass) of mirt objects
ADDED * included item and person fit statistic in 'pcm.fit' 
        for the partial credit model (suggested by Hiroyuki 
        Yamada and Sven Liepertz) 
NOTE  * included C-test dataset 'data.g308' from 
        Schroeders et al. (2014)
NOTE  * included several examples from the book of Eid
        and Schmidt: "Testtheorie und Testkonstruktion",
        see data.eid

DATA  * included/modified datasets: data.g308, data.eid
EXAMP * included/modified examples: pcm.conversion (1),
        pcm.fit (1,2,3), brm.sim (1), data.g308 (1),
        data.eid (1,2)

------------------------------------------------------------------------
Versions 1.1  -- 2014-11-23  --  CRAN sirt 1.1
------------------------------------------------------------------------

NOTE  * included arguments for mean and covariance matrix for
        confirmatory multidimensional models in 'f1d.irt'
NOTE  * removed 'lavaanify.sirt' from sirt package and
        included this function as 'lavaanify.IRT' in 
        TAM package 
FIXED * fixed a bug in 'lavaan2mirt' (thanks to Hong Giang Pham)        
NOTE  * extended some person fit statistics to handle datasets
        with missing responses (thanks to Hiroyuki Yamada)
ADDED * included functions for estimating the Beta item 
        response model for continuous item responses 

DATA  * included/modified datasets: ---
EXAMP * included/modified examples: f1d.irt (2), brm.sim (1)

------------------------------------------------------------------------
Versions 1.0  -- 2014-10-27  --  CRAN sirt 1.0-3
------------------------------------------------------------------------

NOTE  * included argument 'progress' in 'gom.em' for optional
        printing of iteration progress
NOTE  * disabled warnings produced in 'rasch.mirtlc' by the glm
        function 
FIXED * fixed a bug in calculating the posterior in 'mirt.wrapper'
        for nonlinear item response models 
FIXED * fixed a bug in running exploratory factor analysis with
        one dimension in noharm.sirt (thanks to Russell Zheng)
FIXED * fixed a bug in datawide2long with Q-matrix input
FIXED * fixed a bug in data handling in 'invariance.alignment'
        with some missing intercepts and slopes
ADDED * included an extension of lavaan syntax to accomodate
        guessing and slipping parameters and "__" (item shortage 
        declaration) -> function 'lavaanify.sirt'
        The function lavaan2mirt also includes these options.
NOTE  * included coef and vcov method for function 'rasch.evm.pcm'
NOTE  * included argument weights in 'dirichlet.mle'
NOTE  * included utility function for conversion of different
        parameterizations in partial credit model
NOTE  * included helper function 'mirt.wrapper.itemplot'        
NOTE  * enabled progress argument in rasch.copula functions        
NOTE  * renamed DeCarlo's hierarchical rater model based on
        signal detection theory 'rm.hrm' into 'rm.sdt'
NOTE  * fixed an error in description of missing IRT models in
        'rasch.mml2.Rd' (thanks to Carmen Koehler)
NOTE  * fixed a bug in tam2mirt for polytomous items (thanks to
        Michal Modzelewski)
ADDED * included function 'mirt.specify.partable' for modifying
        a parameter table in mirt package 
NOTE  * included argument item type for polytomous data in 'lavaan2mirt'
NOTE  * updated lavaanify.sirt function because of changes in 
        the lavaan::lavaanify function from lavaan 0.5-16 to the
        lavaan 0.5-17 package
NOTE  * changed mean constraint for rater parameters in 'rm.facets' 
ADDED * included estimation and simulation functions for the Nedelsky model
        ('nedelsky.sim', 'nedelsky.irf')

DATA  * included/modified datasets: data.ratings2, data.si06, data.ratings3
EXAMP * included/modified examples: dirichlet.simul (1,2),
        data.read (2), mirt.model.vars (1), rasch.mirtlc (4), 
        data.long (3,4), lavaanify.sirt (1), lavaan2mirt (1),
        dirichlet.mle (1,2), pcm.conversion (1), data.big5 (1),
        mirt.specify.partable (1), nedelsky-methods (1,2)

------------------------------------------------------------------------
Versions 0.47 -- 2014-08-30  --  CRAN sirt 0.47-36
------------------------------------------------------------------------

ADDED * included wrapper function of mirt output of extracting
        item parameters ('mirt.wrapper.coef')
EXAMP * added more examples for model estimation in mirt package
        using customized item response functions and/or 
        customized latent structure distributions
          o Ramsay's quotient model ('sim.qm.ramsay', Example 1)
          o Latent class analysis ('data.read', Model 7)
          o Mixed Rasch model ('data.read', Model 8)
          o Located latent class model/Latent class IRT model
            ('data.read', Model 12; 'rasch.mirtlc', Example 4, Model 4)
          o Probabilistic Guttman model ('prob.guttman', Example 1, 
            Model 3)
          o Nonparametric item response model with monotone item
            response functions ('prob.guttman', Example 4, Model 4)          
          o Discrete grade of membership model ('gom.em', Simulated 
            Example 2, Model 2m)
          o Multimensional item response model with discrete traits
            ('data.read', Model 13)   
          o DINA model ('data.read', Model 14)       
          o Rasch copula model ('rasch.copula2', Example 5)  
          o Rasch model with non-normal distibution ('data.read', Model 15)          
ADDED * included wrapper function of mirt output for extracting
        likelihood, posterior and expected counts 
ADDED * extended modelfit.sirt for fitted objects from mirt package
ADDED * included function 'lavaan2mirt' for converting syntax for the
        lavaan package to syntax for the mirt package
ADDED * included function 'tam2mirt' for converting a fitted object
        in TAM package into an object of class mirt in the mirt package
NOTE  * corrected some typos and improved some examples (thanks to Phil Chalmers)
EXAMP * included an example for running Mplus from within R using the
        MplusAutomation package ('data.read', Model 1)
NOTE  * renamed functionrasch.conquest into R2conquest -> function rasch.conquest
        can still be used
ADDED * included function 'mirt.wrapper.fscores' for computing EAPs, MAPs and MLEs
        for objects of class mirt

DATA  * included/modified datasets: ---
EXAMP * included/modified examples: mirt.wrapper (1,2,3,4,5),
        sim.qm.ramsay (1), modelfit.sirt (1), data.read (1,3,7,8,12,13,14),
        lavaan2mirt (1,2,3), tam2mirt (1,2,3,4), prob.guttman (1), gom.em (2),
        equating.rasch (1), data.reck (2), rasch.mirtlc (4),
        rasch.copula2 (5)

------------------------------------------------------------------------
Versions 0.46 -- 2014-08-05  --  CRAN sirt 0.46-15
------------------------------------------------------------------------

NOTE  * used the operator '::' for functions which are used from 
        other packages than sirt in example files for datasets
FIXED * fixed a bug in plot.noharm.sirt for unidimensional models
NOTE  * fixed a minor bug in summary in 'summary.rasch.pml2'
NOTE  * included argument 'use.maxincrement' for controlling
        increments in 'rasch.pml3'
NOTE  * speeded invariance alignment function and choose now 
        different starting values to ensure a global minimum.
        Changed also default parameters to obtain more
        stable results. 
NOTE  * excluded plotting function of 'invariance.alignment'
NOTE  * changed calculation of measures of noninvariance in
        invariance.alignment. Now, the noninvariance measures 
        in 'invariance.alignment' and 'linking.haberman' 
        are equivalent.

DATA  * included/modified datasets: ---
EXAMP * included/modified examples: data.read, data.big5,
        invariance.alignment (4,5) 

------------------------------------------------------------------------
Versions 0.45 -- 2014-05-30  --  CRAN sirt 0.45-23
------------------------------------------------------------------------

FIXED * fixed a bug in reliability calculation in noharm.sirt
NOTE  * included plots for 'noharm.sirt' using the semPlot package
ADDED * included first version of statistical implicative analysis ('sia.sirt')
ADDED * included function 'rasch.conquest' for running ConQuest from within R

DATA  * included/modified datasets: ---
EXAMP * included/modified examples: data.mixed1, noharm.sirt (1,2),
        sia.sirt (1), data.read, rasch.evm.pcm (4)

------------------------------------------------------------------------
Versions 0.44 -- 2014-04-27  --  CRAN sirt 0.44-48
------------------------------------------------------------------------

FIXED * fixed a bug in calculation of marginal parameters for testlet model
ADDED * included the partially compensatory item response model
        (irtmodel='partcomp' in 'smirt')
NOTE  * speeded rasch.copula functions a bit
NOTE  * included argument increment.factor in rasch.copula to improve
        convergence behavior
FIXED * fixed a bug in rasch.mirtlc in saved parameter estimates for
        models with different initial estimates (n.starts>0)
ADDED * included function for calculating marginal item parameters for
        testlet (bifactor) model ('testlet.marginalized')
ADDED * extended 'modelfit.sirt' for objects of class tam.mml, tam.mml.2pl
        and tam.fa (from the TAM package)
FIXED * fixed a bug in parsing residual matrix from NOHARM output in 'R2noharm'
NOTE  * extended output in mcmc.list. descriptives
NOTE  * changed chi square p value in R2noharm in Values according to summary
ADDED * included R implementation of NOHARM ('noharm.sirt')
NOTE  * modelfit.sirt also allows for objects of class noharm.sirt
NOTE  * included Divgi estimation method of tetrachoric correlation
ADDED * included maximum likelihood estimation of polychoric correlation

DATA  * included/modified datasets: ---
EXAMP * included/modified examples: data.wide2long (1), smirt (3), modelfit.sirt (1),
        R2noharm (4), mcmc.list.descriptives (1), noharm.sirt (1,2), data.read,
        tetrachoric (2), polychoric2 (1)

------------------------------------------------------------------------
Versions 0.43 -- 2014-03-12  --  CRAN sirt 0.43-70
------------------------------------------------------------------------

ADDED * included function 'isop.test' for testing the ISOP model
ADDED * included (non-iterative) eigenvector method for estimating
        the partial credit model -> 'rasch.evm.pcm'
NOTE  * included argument 'ref.item' in rasch.mirtlc for specification
        of reference items
ADDED * included test of de Gooijer and Yuan (2011) that CSN is non-positive
        -> 'unidim.test.csn'   
ADDED * included option for testing differential item functioning in
        rasch.evm.pcm
NOTE  * changed convergence behavior in rasch.mirtlc for 2PL models
ADDED * robust linking alternative to mean-mean linking ('linking.robust')
NOTE  * corrected output for hierarchical rater model ('rm.hrm')
ADDED * included simple latent class model for two exchangeable raters 
        ('lc.2raters')
ADDED * extended unidimensional copula model to multiple dimensions ('rasch.copula3')
NOTE  * changed numerical differentiation parameters in several functions
        to a smaller value
ADDED * included missing data IRT model ('rasch.mml2', irtmodel='missing1')
NOTE  * included person (containing person parameters) as a value in rasch.copula2
        and rasch.copula2
FIXED * fixed a bug in testlet.yen.q3
NOTE  * allowed correlated residuals in reliability calculation of 'reliability.nonlinearSEM'
NOTE  * included reliability estimation for pseudo maximum likelihood estimation (rasch.pml3)
NOTE  * included marginal item parameters in the output in testlet model (mcmc.3pno.testlet)

DATA  * included/modified datasets: data.reck73C1a, data.reck73C1b,
        data.reck75C2, data.reck78ExA, data.reck79ExB, 
        data.liking.science, data.si02, data.si03, data.si04, data.si05
EXAMP * included/modified examples: isop.test (1), rasch.evm.pcm (1,2,3,4,5,6),
        data.reck (2,3), rasch.mirtlc (3,4,5), gom.em (2), unidim.test.csn (1,2),
        gom.em (1), linking.robust (1,2,3), lc.2raters (1), data.wide2long (2),
        rasch.copula (4), rasch.mml2 (7), reliability.nonlinearSEM (1)  

------------------------------------------------------------------------
Versions 0.42 -- 2014-01-31  --  CRAN sirt 0.42-25
------------------------------------------------------------------------

NOTE  * included further values in smirt to allow to apply itemfit.sx2
        in the CDM package
FIXED * fixed a bug in output of person parameters in smirt (missing
        standard errors; thanks to Balal Izanloo)
NOTE  * included empirical item-attribute discriminations in lsdm
NOTE  * changed NAMESPACE and DESCRIPTION files due to a change in Rcpp
FIXED * fixed a bug for constraint in mu for multidimensional models
        in rasch.mml2
FIXED * fixed warning messages when reading NOHARM output files
NOTE  * stabilized estimation of tetrachoric correlation coefficients
        for Tucker method (addition of cell sizes with a value .5) 
ADDED * included the method of Bonett and Price for calculation a
        tetrachoric correlation
NOTE  * included additional outputs and item parameters for the 
        HRM-SDT (thanks to a discussion with Robin Gleeson)
NOTE  * extended modelfit.sirt to objects of class R2noharm

DATA  * included/modified datasets: data.timss07.G8.RUS, data.reck611
EXAMP * included/modified examples: fuzcluster (1), modelfit.sirt (1)

------------------------------------------------------------------------
Versions 0.41 -- 2014-01-07  --  CRAN sirt 0.41-21
------------------------------------------------------------------------

ADDED * included maximum likelihood estimation for discrete data in the
        belief function framework ('fuzdiscr')
ADDED * included pseudo-log-likelihood estimation for fractional item
        responses (values between 0 and 1) in 'rasch.mml2'
ADDED * included clustering fur fuzzy continuous data (belief function
        framework) ('fuzcluster')

DATA  * included datasets: data.pirlsmissing
EXAMP * included examples: mcmc.2pno.ml (3), rasch.mml2 (7)

------------------------------------------------------------------------
Versions 0.40 -- 2013-12-09  --  CRAN sirt 0.40-9
------------------------------------------------------------------------

FIXED * fixed a bug in 'data.wide2long'
NOTE  * changed Rcpp code in eigenvalue calculation due to a CRAN request

DATA  * included datasets: data.big5.qgraph 
EXAMP * included examples: ---

------------------------------------------------------------------------
Versions 0.39 -- 2013-11-17  --  CRAN sirt 0.39-30
------------------------------------------------------------------------

NOTE  * included approximating function of expected percent score in
        truescore.irt
NOTE  * added a check function for inits in smirt (thanks to Balal Izanloo)
FIXED * fixed a bug in output of person parameters (thanks to Balal Izanloo)
NOTE  * speeded latent regression model 'latent.em.regression.raschtype'
ADDED * included latent.em.regression.normal for normally distributed
        outcomes
NOTE  * included factor for convergence acceleration in invariance.alignment
NOTE  * included summary for latent regression models
ADDED * included function 'mle.pcm.group' for maximum likelihood estimation
        in generalized item response models which includes an option for
        estimating group parameters
NOTE  * changed algorithm in 'invariance.alignment' into a two-step approach
NOTE  * included plot method for function 'invariance.alignment'

DATA  * included datasets: data.inv4gr, data.ess2005, data.mcdonald.rape,
        data.si01 
EXAMP * included examples: lsdm (4,5), invariance.alignment (3),
        plausible.value.imputation.raschtype (2,3)

------------------------------------------------------------------------
Versions 0.38 -- 2013-10-23  --  CRAN sirt 0.38-25
------------------------------------------------------------------------

ADDED * included function for automated finding of a scoring key in
        a data frame with raw item responses ('automatic.recode')
FIXED * fixed a bug in linking.haberman function 
NOTE  * added argument personpars in linking.haberman for transformation
        of person parameters
ADDED * included alignment method for approximate invariance
        (Asparouhov & Muthen, 2013)
ADDED * included function truescore.irt for conversion of trait scores
        into true scores for unidimensional item response models

DATA  * included item parameters data.activity.itempars

------------------------------------------------------------------------
Versions 0.37 -- 2013-10-02  --  CRAN sirt 0.37-24
------------------------------------------------------------------------

FIXED * fixed a bug in rasch.mirtlc with multiple starts in latent
        class models
NOTE  * allowed input of student weights and product-moment
        matrix in R2noharm
FIXED * fixed a bug in calculation of degrees of freedom in R2noharm 
        function
FIXED * fixed a bug in linear transformation for person parameters
        in linking.haberman
ADDED * included eigenvalue decomposition function 'eigenvalues.sirt'

DATA  * included datasets: 'data.noharmExC', 'data.mcdonald', 'data.reck'
DATA  * included data conversion function 'data.wide2long'  
DATA  * renamed 'data.noharm' into 'data.noharm18'  
  
------------------------------------------------------------------------
Versions 0.35/0.36 -- 2013-09-08  --  CRAN sirt 0.36-30
------------------------------------------------------------------------

NOTE  * corrected legends and labels in plot.isop function
ADDED * included function rowKSmallest2.sirt
FIXED * fixed a bug in mcmc.3pno.testlet (thanks to Chun-Hsien Wu)
        -> removed parametrization 3 (bifactor model) because it
        produced untrustworthy results
NOTE  * included gregmisc in imports (thanks to Jean-Paul Fox)
NOTE  * disabled parametrization 2 in mcmc.3pno.testlet
        -> now only the original model from the Glas paper
          (parametrization 1) is estimated
NOTE  * included argument for item parameter fixings in
        pairwise conditional likelihood function rasch.pairwise.itemcluster
NOTE  * included ETS classification labels of uniform DIF in
        function dif.logistic.regression
NOTE  * included the option of not submitting any item strata 
        to stratified.cronbach.alpha and an example for using 
        the psych package
ADDED * included function 'md.pattern.sirt' for analyzing
        response patterns
NOTE  * included crossprod function in several sirt functions
ADDED * included monotone nonparametric estimation in 'rasch.mml2'
        as the default in case of irtmodel='npirt' and npformula=NULL
NOTE  * speeded irtmodel='npirt' in case of providing npformula
NOTE  * included output of summary of testlet effects in 
        mcmc.3pno.testlet
ADDED * included the functional unidimensional model (Ip et al. 2013)
ADDED * included the linking method of Haberman (2009)
NOTE  * included plot method for rasch.mml2 function
NOTE  * removed rasch.testlet.glmer function

------------------------------------------------------------------------
Version 0.34 -- 2013-08-13  --  CRAN sirt 0.34-46
------------------------------------------------------------------------

ADDED * included estimation of ISOP and ADISOP models
FIXED * fixed a bug in pbivnorm2 for negative correlations
NOTE  * included argument increment.factor in smirt to
        prevent nonconvergence (thanks to Balal Izanloo)
ADDED * included rowwise maximum and minimum and rowwise
        cumulative sum of a matrix based on Rcpp code
ADDED * included matrix functions rowIntervalIndex.sirt 
        (useful for simulations) and rowKSmallest.sirt 
        (useful for sorting matrix entries, e.g. for
        predictive mean matching in mice)
FIXED * fixed a bug in mcmc.2pno.ml (thanks to Ronny Scherer)
ADDED * included matrix row and column wise monotone regression
        function monoreg.rowwise (adapted from fdrtool package)
ADDED * included graded response model estimation in isop.poly
        function
ADDED * included plot method for ISOP models (isop.dich and
        isop.poly)

DATA  * included example data.big5
EXAMP * included an example for DETECT for polytomous data

------------------------------------------------------------------------
Versions 0.32/0.33 -- 2013-07-09  --  CRAN sirt 0.33-16
------------------------------------------------------------------------

ADDED * included the estimation  of the 2PL model via MCMC (mcmc.2pno)
NOTE  * included a function for estimating Rhat and MAP from MCMC output
        (mcmc.list.descriptives)
ADDED * included a function for writing coda files (mcmclist2coda)
NOTE  * renamed jacknife.rasch.jml into rasch.jml.jackknife1
ADDED * included mcmc.2pnoh for estimating a hierarchical IRT model
ADDED * included mcmc.3pno.testlet for estimating IRT testlet and
        bifactor models for dichotomous data
ADDED * included mcmc.2pno.ml function for estimating a multilevel
        IRT model for dichotomous and normally distributed data
ADDED * included R2NOHARM functions into this package for running
        NOHARM from within R
NOTE  * modelfit.sirt now allows objects of class smirt
NOTE  * speeded calculation of modelfit.sirt
NOTE  * speeded rasch.mml2, prob.guttman, rasch.mirtlc, rm.facets, rm.hrm

------------------------------------------------------------------------
Version 0.31 -- 2013-05-27  --  CRAN sirt 0.31-20
             [*** First CRAN Release ***]
------------------------------------------------------------------------

NOTE  * speeded rasch.pml2 a bit
FIXED * fixed a bug in smirt function (thanks to Izanloo Balal)
ADDED * included function tetrachoric2 faster calculation
        of the tetrachoric correlation matrix
ADDED * included pbivnorm2 for calculating the bivariate normal integral
NOTE  * included rasch.pml3, a bit faster version than rasch.pml2
FIXED * eliminated warning statements in smirt and fixed a bug in 
        estimation of a and b parameters in smirt (thanks to Izanloo Balal)

------------------------------------------------------------------------
Version 0.30  -- 2013-04-30
------------------------------------------------------------------------

NOTE  * included a Rcpp function for faster calculations in rm.hrm
        (now there is a dependency of Rcpp and RcppArmadillo)
ADDED * included smirt function for estimating the multdimensional
        noncompensatory and compensatory models
ADDED * included variational approximation for the Rasch model
ADDED * included the (Rasch) grade of membership model

------------------------------------------------------------------------
Version 0.29  -- 2013-04-08
------------------------------------------------------------------------

ADDED * included function for computing eigenvalues and inverses of
        many matrices
ADDED * included facets models with item/rater intercepts and slopes
ADDED * included initial version of the hierarchical rater model based on
        signal detection theory (DeCarlo et al., 2011)
ADDED * included function for simulating and estimating the
        Dirichlet distribution
ADDED * included grade of membership model with joint maximum 
        likelihood estimation -> gom.jml

------------------------------------------------------------------------
Version 0.28  -- 2013-03-24
------------------------------------------------------------------------

NOTE  * included standard errors in rasch.mml2
ADDED * included marginal true score reliability for binary item 
        response data (Dimitrov, 2003; thanks to Ulrich Schroeders)

------------------------------------------------------------------------
Version 0.27  -- 2013-02-26
------------------------------------------------------------------------

ADDED * included classification accuracy in the Rasch model
ADDED * implemented the multidimensional latent class Rasch model
        (Bartolucci, 2007)
NOTE  * cleaning of help files, included several datasets and
        examples
NOTE  * included log-linear smoothing of the theta distribution
        in rasch.mirtlc
ADDED * included 2PL estimation in rasch.mirtlc
ADDED * included global fit statistics in modelfit.sirt
NOTE  * included log-linear smoothing of the ability distribution
        in rasch.mml2
NOTE  * accelerated rasch.pml function and renamed it into rasch.pml2
NOTE  * allowed for linear constraints for residual correlations
        in rasch.pml2
NOTE  * accelerated latent.regression.em.raschtype and 
        plausible value routines

------------------------------------------------------------------------
Version 0.26  -- 2013-01-17
------------------------------------------------------------------------

NOTE  * restructured rasch.mml2 function to get a bit more compact code
NOTE  * do not export rasch.mml and rasch.copula anymore via namespace
ADDED * included nonparametric IRT function estimation in rasch.mml2
        -> argument irtmodel='npirt' (Rossi, Wang & Ramsay, 2002)
ADDED * included multidimensional models in rasch.mml2
NOTE  * added corrected AIC (AICc) in rasch.mml2 and rasch.copula2
NOTE  * corrected mean and SD estimation in rasch.mml2
FIXED * fixed a bug in the calculation of the number of estimated parameters
        in rasch.copula2
FIXED * corrected rasch.mml2 function in case of fixed weights of
        trait distribution
FIXED * corrected a bug in wle.rasch
ADDED * included probabilistic Guttman model
ADDED * added analytical bias correction method for JML estimation of the Rasch model
NOTE  * accelerated PMML estimation algorithm
ADDED * added 2PL estimation in rasch.pml

------------------------------------------------------------------------
Version 0.25  -- 2012-10-16
------------------------------------------------------------------------

FIXED * fixed bad numerical behavior in rasch.copula2 for Cook-Johnson
        and Frank copula models
NOTE  * improved speed in yen.q3 and extended output
NOTE  * speed improvement in rasch.mml and rasch.copula2
NOTE  * included version rasch.mml2 with substantial speed improvements
NOTE  * speed improvements for rasch.jml function

------------------------------------------------------------------------
Version 0.24 -- 2012-09-20
------------------------------------------------------------------------

NOTE  * changed algorithms behavior of rasch.copula2 
        (parameter increments depend on number of iterations)
FIXED * corrected deviance calculation in rasch.copula

------------------------------------------------------------------------
Version 0.23  -- 2012-08-31
------------------------------------------------------------------------

NOTE  * removed functions for running ConQuest from this package
ADDED * included Cook-Johnson and Frank copula in rasch.copula2 function
ADDED * included examples for wle.rasch.jackknife
FIXED * removed a minor printing bug in rasch.copula
FIXED * fixed a bug in jackknife.rasch.jml
NOTE  * included item parameter constraints in jackknife.rasch.jml
FIXED * corrected handling of extreme responses in rasch.prox

------------------------------------------------------------------------
Version 0.22 -- 2012-07-17
------------------------------------------------------------------------

ADDED * included estimation of residual error correlations in rasch.pml
NOTE  * restructured rasch.testlet.glmer function
DATA  * included data set reading data.read
NOTE  * set a different default in rasch.mml (estimation of trait SD seemed incorrect)
NOTE  * rasch.testlet.glmer: output EAPs and EAP reliability
NOTE  * included loglog and cloglog link functions in rasch.testlet.glmer
ADDED * included jackknife estimation of the joint maximum likelihood
        Rasch model
NOTE  * included a speeded version of rasch.copula and labelled it 
        as rasch.copula2 -> The old version rasch.copula remains in the package.
NOTE  * output posterior distribition, EAP estimates and
        EAP reliability in rasch.copula    
ADDED * introduced probit and logit version of rasch.pml: pairwise marginal 
        likelihood estimation
FIXED * removed some bugs (or inefficiencies) in numerical differentiation 
        in rasch.mml and rasch.copula
NOTE  * renamed sim.rasch.copula into sim.rasch.dep
ADDED * included function rasch.pairwise.itemcluster for the conditional 
        pairwise estimation method for locally dependent items   
NOTE  * package structure of sirtr is created
ADDED * included simulation function for Rasch copula model ('sim.rasch.copula')


**************************************************************************
# older sirt versions (formerly sirtr up to 0.21)

Version 0.21 -- 2012-06-23
Version 0.20 -- 2012-06-18
Version 0.19 -- 2012-04-26
Version 0.18 -- 2012-03-29
Version 0.17 -- 2012-02-22
Version 0.16 -- 2012-02-17
Version 0.15 -- 2011-12-19
Version 0.14 -- 2011-10-06
Version 0.13 -- 2010-08-26
Version 0.12 -- 2010-01-13
Version 0.11 -- 2010-01-12
Version 0.10 -- 2010-01-02
Version 0.9  -- 2009-11-01
Version 0.8  -- 2009-03-08
Version 0.7  -- 2009-03-02
Version 0.6  -- 2009-12-02
Version 0.5  -- 2008-11-12
Version 0.4  -- 2008-08-25
Version 0.3  -- 2008-05-06
Version 0.2  -- 2008-01-29
Version 0.1  -- 2007-12-22
Version 0.0  -- 2007-12-18