One-Parameter Logistic Model and its Application in Test Development

Research Paper

Abstract

The study focused on the one-parameter logistic model (1PLM) and its’ application in test development. Two research questions were answered and the design of the study was the instrumentation. Instrumentation research is a scientific investigation for meticulous development or construction of a test or measuring instrument that validity measures that concept or psychological construct, which it intends to measure with all accuracy (Kpolovie, 2010). A multi-stage sampling technique was used to acquire a sample size of 200 students for the study. A simple random sampling technique was used to select four schools from the local government area. Stratified random sampling was used to select 50 students each from each of the four schools to give the needed sample of 200 for the study. The instrument for this study was a self-developed mathematics test items. It is a 50 items test. The format is multiple-choice objectives with five (5) options lettered A-E. Findings revealed that the use of one parameter latent trait theory (Rasch model) offers the opportunity to deal with core measurement issues such as construct validity as well as providing richer interpretation regarding examinee performance.