TwoPLM {exametrika} | R Documentation |
Two-Parameter Logistic Model
Description
The two-parameter logistic model is a classic model that defines the probability of a student with ability theta successfully answering item j, using both a slope parameter and a location parameter.
Usage
TwoPLM(a, b, theta)
Arguments
a |
slope parameter |
b |
location parameter |
theta |
ability parameter |
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^{-a(\theta-b)}}
[Package exametrika version 1.5.1 Index]