OscatsModelL1p

OscatsModelL1p — One-Parameter Logistic (1PL) Model

Synopsis

struct              OscatsModelL1p;

Object Hierarchy

  GObject
   +----OscatsModel
         +----OscatsModelL1p

Description

Details

struct OscatsModelL1p

struct OscatsModelL1p;

The One-Paramter Logistic (Rasch) IRT model: P(X=1|theta) = 1/1+exp[-(sum_i theta_i -b + sum_j d_j covariate_j)], where b is the item difficulty. Distance is defined as: abs(sum_i theta_i - b + sum_j d_j covariate_j).

Parameter names: Diff.

References:

R. J. de Ayala (2009). The Theory and Practice of Item Response Theory. p 15.

G. Rasch (1980). Probabilistic Models for Some Intelligence and Attainment Tests.