algo_effectiveness      Computes the actual and predicted effectiveness
                        of a given algorithm.
classification          A dataset containing classification algorithm
                        performance data.
effectiveness           Computes the actual and predicted effectiveness
                        of the collection of algorithms.
irtmodel                Fits a polytomous IRT model.
make_polyIRT_data       Converts continuous performance data to
                        polytomous data with 5 categories.
model_goodness          Computes the goodness of IRT model for all
                        algorithms.
model_goodness_for_algo
                        Computes the goodness of IRT model for a given
                        algorithm.
prepare_for_plots       Utility function to make a dataframe from the
                        IRTmodel
