search for: lordif

Hi All, ? I am trying to use the lordif package in R and can't figure out the reason for the above error when I try to run the calctheta() function. ################## # read data using foreign package - must be Stata 11 or earlier racedata<- read.dta("race.dta")??? # item responses resp.data<-racedata[,-c(1:2)...

Hi all I am not an experienced user of R. I am trying to perform DIF analysis using Lordif and I get the follow error: > GroupDIF <- lordif(resp.data=Resp, group=Group, criterion="R2", pseudo.R2="McFadden", R2.change=0.02) Iteration: 500, Log-Lik: -137340.437, Max-Change: 0.00119 EM cycles terminated after 500 iterations. (mirt) | Iteration: 1, 14 items flagge...

...s on how to conduct a proper DIF analysis starting from a model of class gpcm (from the wonderful package ltm by prof. Rizopoulos)? difR will handle only dichotomous items, and I have a mix of dicho- and polytomous ones (that's why I chose the partial credit model). I also found the package lordif, but I'm not really sure if that's what I need. I basically want to regress item difficulties on some other covariates (sex, age class,...).. Is there a package you know of that handle such models for a DIF analysis or should I code such a thing by myself? and if so, how can I extract wha...

...oPlotR (0.5.1), GEOmap (1.5-9), GEVcdn (1.0.2), GillespieSSA (0.5-4), gllm (0.33), glmperm (1.0-3), gRapHD (0.1.7), HFWutils (0.9.4.2010.08.20), hts (1.3), HWEintrinsic (1.1.1), igraph (0.5.4-1), intervals (0.13.3), ipw (1.0-6), laeken (0.1.3), LDheatmap (0.2-9), lme4 (0.999375-35), lmPerm (1.1-2), lordif (0.1-6), lpSolveAPI (5.5.2.0), magma (0.2.1-3), MCMCglmm (2.06), mondate (0.9.08.15), mondate (0.9.08.19.02), mratios (1.3.13), nacopula (0.4-3), nleqslv (1.7), nlt (2.1-1), NMF (0.5), pROC (1.3.1), qpcR (1.3-1), qpcR (1.3-0), qtl (1.18-7), qualityTools (1.01), R.utils (1.5.0), r4ss (1.10), rAverag...

CRAN (and crantastic) updates this week New packages ------------ * EffectStars (1.0) Maintainer: Unknown Author(s): Gunther Schauberger License: GPL-2 http://crantastic.org/packages/EffectStars The package provides functions to visualize regression models with categorical response. The effects of the covariates are plotted with star plots in order to allow for an optical

CRAN (and crantastic) updates this week New packages ------------ * bdoc (1.0) Michael Anderson http://crantastic.org/packages/bdoc This package contains a function that will classify DNA barcodes as well as a few test and reference data sets. * bdsmatrix (1.0) Terry Therneau http://crantastic.org/packages/bdsmatrix This is a special case of sparse matrices, used by coxme and

...eR (1.0), lasso2 (1.2-11), latentnet (2.3-0), lattice (0.18-8), latticedl (1.1), latticeExtra (0.6-11), latticist (0.9-43), lda (1.2.1), ldDesign (1.2-0), lemma (1.3-1), lgtdl (1.1.1), limSolve (1.5.2), linprog (0.9-0), lme4 (0.999375-34), logging (0.4-42), logistf (1.10), longitudinalData (0.6.5), lordif (0.1-5), ltm (0.9-4), maanova (1.18.0), MAc (1.1), MAd (0.8), mapdata (2.1-3), maps (2.1-4), maptools (0.7-34), marelac (2.1), MASS (7.3-7), Matrix (0.999375-42), matrixStats (0.2.1), maxLik (0.7-2), mbmdr (2.1), mboost (2.0-6), mc2d (0.1-8), mclust (3.4.4), mcmc (0.8), mco (1.0.9), mecdf (0.4.1),...