Calculates the item success probability under the 2PL model.
Calculate2plProb(thetaValue, itemParameters, logistic = TRUE)A numeric value or array for the theta (ability) value(s) where the difference will be calculated
A matrix containing the numeric values of item discriminations on the first column and item difficulties on the second
A logical value stating if the IRT model will use the logistic or the normal metric.
probabilities A numeric matrix with the probabilities on each thetaValue for each item.
de Ayala, R. J., (2009). The theory and practice of item response theory. New York: The Guildford Press