Changes in Version 0.13-0
  o LLTM, LRSM, and LPCM work now for repeated measurement designs with treatment groups and missing values.
  o Rename vignette to 'eRm'.  


Changes in Version 0.12-2

  o new function plotPWmap to plot Bond-and-Fox style
    pathway maps for the data by Julian Gilbey. Since
    calculation of the t-statistics requires calculation
    of the kurtosis of the standardized residuals,
    according changes to itemfit.ppar, personfit.ppar,
    pifit.internal, print.ifit, and print.pfit.

  o plotPImap patched by Julian Gilbey: length of item.subset
    did not match the documentation, warning stars did not all
    appear, pre-calculated person.parameter data can be passed
    to the function via pp, mis-ordered items can be coloured.
    some minor bugs fixed.

  o the optimizer can be changed to optim using fitctrl<-"optim"
    and reset to nlm (the default) with fitctrl<-"nlm"

  o value of LRtest now countains the list fitobj which contains
    the model objects according to the subgroups specified by
    splitcr

  o MLoef no longer supports missings values

Changes in Version 0.12-1

  o function invalid from package gtools integrated into eRm
    eRm no longer depends on gtools

Changes in Version 0.12-0

  o for RM, RSM, and PCM: eta parameters are now
    diplayed as difficulty parameters
    print and summary methods changed accordingly

  o new labeling of eta parameters in RM, RSM, and PCM.
    they now are labeled according to the estimated
    parameters for items (RM), items + categories (RSM),
    items x categories (PCM)

  o function MLoef for Martin-Loef-Test added

  o df in personfit and itemfit corrected

  o the logLik functions now extract the log-likelhood
    and df into objects of class logLik.eRm and loglik.ppar
    with elements loglik and df. the corresponding
    print methods have been modified accordingly.

  o function coef.ppar to extract person parameter estimates added

  o option for beta parameters added to coef.eRm

  o in confint.eRm: default parm = "beta"

  o minor modifications in the help file for IC()

  o plotPImap: revised rug added, bug concerning item.subset fixed,
    minor modifications to enhance readability

  o minor modifications in plotjointICC: allows for main title and colors,
    option legpos = FALSE suppresses legends, dev.new removed,
    legend = FALSE produced incorrect labeling

  o minor modifications in plotICC: allows for main title and colors,
    default coloring with col = NULL instead of NA for compatibility,
    option legpos = FALSE suppresses legends, mplot is now FALSE if
    only one item is specified

  o plot.ppar: dev.new removed

  o option 'visible' in print.ifit und print.pfit to allow for avoiding
    overly long output and for extraction of infit and outfit values
    (maybe changed to a coef method later)

  o strwrap() for NPtest print methods to break long lines

  o new methods IC.default and pmat.default for enhanced error messages

  o lazy loading package and datafiles

