Validity and reliability of instrument competencies framework of agriculture educators: the Rasch Measurement Model

Abstract

This study aims to produce empirical evidence of the validity and reliability of instrument items for the competency framework of agricultural teaching staff in Malaysian agricultural vocational colleges. The validity and reliability of the framework were analyzed using Rasch Model Measurement assisted by Winsteps 3.72 software. This research instrument contained 116 items, which was distributed to 30 instructors at the Teluk Intan Agricultural Vocational College, Malaysia. The selection of respondents was made by strata random where the researcher makes the strata of the population according to the percentage and then selects randomly based on the desired percentage. Validity analysis of the instrument was done through four functional testings. For reliability and separation of respondents, it was found that the individual reliability value was very good and acceptable. The results of the item polarity analysis detected no negative value (-) in the Point Measure Correlation value. Item matching analysis found that 11 items had to be dropped as they failed to meet the required conditions. From the analysis on local dependence that determines dependent items based on the standardized residual correlation value, it was discovered that the correlation value for the items used was detected; 13 items need attention. The results of the data analysis checking the functionality of the items suggested that some items should be dropped. The omission of these items has provided evidence that the instrument of competence of agricultural instructors is crucial to have a high level of validity and reliability for use in actual studies.