The one-parameter logistic model is a model with only one parameter b. This model is a 2PLM model in which a is constrained to 1. This model is also called the Rasch model.
Value
Returns a numeric vector of probabilities between 0 and 1, representing the probability of a correct response given the ability level theta. The probability is calculated using the formula: \(P(\theta) = \frac{1}{1 + e^{-(\theta-b)}}\)
Note
This function will be removed in exametrika 3.0.0. It is a special case of LogisticModel, which covers the 1PL to 4PL models; use that instead.