betafunctions v. 1.3.0

• Fixed some typographical errors in documentation.

• Minor modification to LL.CA() where the function now won’t automatically terminate if true-score distribution fitting procedure produces NA or NaN estimates.

  • True-score distribution fitting now performed using the new Beta.tp.fit() function.

  • The grainsize argument is now fully removed from LL.CA().

  • Added additional checks and diagnostics in LL.CA(), issuing warnings for aberrant events.

  • If a list of parameter values are supplied in place of a score-vector, it is now necessary to supply an etl (effective test length) parameter as well. See documentation for the ETL() function for more information.

• Fixed an error in the fitting procedure of Beta.4P.fit() which occurred during positive skew.

• Added the Beta.tp.fit() function for estimating four-parameter Beta distribution parameters for an underlying true-score distribution, assuming that the observations are generated from data generated from a Beta-Binomial model.

betafunctions v. 1.2.1

• Fixed the LL.ROC() function which stopped working after the previous update.

  • Included possibility of specifying the number of points for which the ROC curve is drawn and the AUC statistic is calculated by way of the new grainsizeargument.

betafunctions v. 1.2.0

• Added functionality for calculating consistency statistics by way of the new ccStats() function.

• Substantial developments concerning primarily the LL.CA() function, adding functionality and improving performance.

  • Added calculation of consistency statistics by calling the new ccStats() function.

  • Added output argument indicating which statistics to calculate. Default is to compute both accuracy and consistency.

  • Calculation of distribution-based output now utilizes the integrate() function.

    • Subsequently rendered the grainsize argument inert, as it was used for the previous method.

  • Added possibility of supplying list of custom parameter values for the four-parameter Beta true-score distribution, forgoing the need to estimate one.

  • Added override argument providing the possibility of overriding the default fail-safe reverting to a two-parameter Beta true-score distribution, should the fitting procedure produce impermissible parameter estimates.

betafunctions v. 1.1.0

• Fixed small typographical errors in documentation.

• Added the cba() function for computing Cronbach’s alpha.