The One-Parameter Logistic Model (1PLM) And Its Application In Test Development

Abstract

Recent development in the measurement field has led to the development of various measures for the purpose of constructing and validating assessment instruments. One of such is the most popularitem response theory (IRT). Various models have been developed for the IRT of which the one parameter logistic model (1PLM)is part. This paper gives a brief overview of the 1PLM focusing on explaining the theoretical perspectives, the assumptions underlying it, the item characteristic curve as well as an illustrative example in the calculation of the 1PLM.The model promises to be one effective way of examining the relationship between examinees ability and his/her performance on a given task and a potential guide for test development.