[R-pkgs] irtoys 0.1.4
Ivailo.Partchev at psy.kuleuven.be
Thu Jun 23 11:37:02 CEST 2011
A new version of irtoys is / will be available on CRAN. Two minor bugs have been fixed. One of these is more interesting: the previous code did not anticipate negative estimates for discriminations. What I did not know is that, unlike ICL or Bilog, ltm does not constrain discriminations to be positive. This means that it can be used to analyze bipolar data (think political sciences).
There are also two new features: (i) Tamaki Hattori has kindly provided me with the original 1980 article of Haebara, and he has written code for the symmetrical versions of the Haebara and Stocking-Lord scaling methods, now available as an option; (ii) I have finally added a wle function for the bias-corrected estimates of ability aka Warm's estimates
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