Using Rasch Model to Detect Differential Person Functioning and Cheating Behavior in Natural Sciences Learning Achievement Test

Purwo Susongko,Heru Widiatmo,Mobinta Kusuma

doi:10.30870/jppi.v5i2.5945

Abstract

The existence of abberant response showed the inaccuracy of measurement which, in turn, threatens the test validity. This study aims at: (1) Discovering the proportion of students who were having Differential Person Functioning (DPF) in final term assessment test of natural sciences course for 8th grade in odd semester of academic year 2016/2017 in Tegal Regency, Indonesia; (2) Identifying the students suspected of cheating during the final term assessment test of natural sciences course for 8th grade in odd semester of academic year 2016/2017 in Tegal Regency, Indonesia. This research involved 1011 student responses to final term assessment test of natural sciences course for 8th grade in odd semester of academic year 2016/2017 in Tegal Regency, Indonesia. The data were taken from four junior high schools; SMPN I Dukuhturi, SMPN I Suradadi, SMPN 2 Slawi and SMPN 2 Dukuhwaru. The scoring was done using Rasch model and the person fit index used Sijtsma’s Ht person fit statistic (Ht). The result showed: (1) 14% of the students attending final term assessment of natural sciences course for 8th grade in the odd semester of academic year 2016/2017 in Tegal Regency, Indonesia were detected of having DPF. From the four junior high schools involved in the research, three junior high schools have a proportion of students having DPF at a range from 9.6% to 23%, and only 1.1% of the other one’s students were having DPF; (2) Nine pairs of students were suspected of cheating during the final term assessment of natural sciences course for 8th grade in the odd semester of academic year 2016/2017 in Tegal Regency, Indonesia.

Highlights

One of the main functions of learning achievement test is to determine students’ final competence achievement and the result could be used to consider to promote them to higher class, to declare their graduation of a school, to grant them a certain certificate
This research aims at: (1) Discovering the proportion of students who are having Differential Person Functioning (DPF) in final term assessment test of natural sciences course for 8thin odd semester of academic year 2016/2017 in Tegal Regency, (2) Identifying the students suspected of cheating during the final term assessment test of natural sciences course for 8th grade in odd semester of academic year 2016/2017 in Tegal Regency, Indonesia
To detect the possibility of cheating behavior on students used some criteria: (1) it is happened to students who sit close each other by looking at their test numbers and the same scores; (2) Copier defined by looking at students Ht index under cut off boundary from Person Fit Score/ PFS and considering appearing of person-response functions (PRF), (3) Source of cheating sheets defined by looking at students Ht index above cut off boundary of PFS and considering appearing

Summary

Introduction

One of the main functions of learning achievement test is to determine students’ final competence achievement and the result could be used to consider to promote them to higher class, to declare their graduation of a school, to grant them a certain certificate. To discover further the construct validity of substantive aspect of Final Term Assessment administered in Tegal Regency so far, detecting DPF in participants needs to be done to figure out the cause of abberant responses from the students.

Objectives

Results

Conclusion