PARAMETER ESTIMATION METHOD IN ITEM RESPONSE THEORY

摘要

PROBLEM TO BE SOLVED: To provide an innovative method enabling parameter estimation in an item response theory without using an unstable numerical technique.;SOLUTION: The model of the item response theory when a reaction pattern is set to be u_j(=1: a correct answer to the item j, =0: an incorrect answer to the item j) is expressed by a formula P(u_j=1|θ_i)=1/(1+exp(-a_jθ_i+b_j)) in which the capability parameter of a learner (i) is θ_i and which has characteristic parameters of the item j, a_j and b_j. When reaction data to (m) items are obtained, the parameter a_j is estimated by the standard deviation of logarithm of the odds calculated from conditional probability of reaction pattern appearance frequency.;COPYRIGHT: (C)2008,JPO&INPIT