Comparative Effectiveness of Logical-choice Weight and Confidence Scoring Methods on Reliability and Validity of Chemistry Multiple-choice Test Items in Nigerian Secondary Schools

Abstract

This study compared the effectiveness of Confidence Scoring Method (CSM) and Logical-choice Weight Method (LWM) of scoring objective tests in Chemistry. It examined which of the two scoring methods is more effective, reliable and valid. These were with a view to enhancing the reliability and validity of Chemistry objective test for standard assessment. The population for the study comprised of Senior Secondary School two (SSS II) students in Osun State. The sample consists of 280 SSSII Chemistry Students in their intact classes from four randomly selected schools and in four randomly selected local government areas of the state. The classes were randomly assigned to the two scoring methods. The instruments used for the study were Chemistry Multiple-choice Test type A and B (CMTA and CMTB). The 40-item Chemistry multiple-choice test was administered on the students in each school. Two scoring methods were used to score the test items. Data collected were analyzed using formula and Fisher z-test. Results obtained revealed that significant difference existed in the reliability coefficient of CSM and LWM of scoring (z 2 =7.82; p<0.05). Also, a significant difference existed between CSM and LWM in the validity coefficient (z 2 =5.2; p<0.05). It was found that CSM was better in the reliability and validity of the test scores ((CSM: z=2.903; LWM: z=0.847 (for reliability) and CSM: z=2.568; LWM: z=0.239 (for validity)). It was therefore concluded that CSM could be used to authentically assess Chemistry students' performance and able to identify students with genuine learning difficulties.