The purpose of the study was to analyse the psychometric qualities of practical physics questions of West African Examination Council and National Examinations Council using the Partial Credit Model (PCM). The objectives of the study were specifically to evaluate the Standard Error of Measurement (SEM), the fit statistics and item difficulty estimates of WAEC and NECO practical physics items and also to test for significance difference of NECO, WAEC and NECO-WAEC psychometric qualities in various years. The apparent difference in the public image of WAEC and NECO examinations, the neglect of psychometric analsyis of polytomously scored physics items and the absolute importance of psychomotor assessments in physics, motivated the researcher to carry out this study. The design of the study was instrumentation research design and the area of the study was Enugu State of Nigeria. The population of the study was all SS III physics students of 2012/2013 academic session in Enugu State. A sample of 668 physics students was drawn through multi stage sampling procedure. The instrument for the study consisted of four different tests viz; two practical physics questions of NECO 2011 and 2012 (PPQN, 1 and 2) and two practical physics questions of WAEC 2011 and 2012 (PPQW, 1 and 2). Eight research questions and nine hypotheses guided the study. The research questions were answered using the descriptive statistics of Winstep software maximum likelihood ratio. The hypotheses were tested at 0.05 level of significance using the SPSS independent sample t-test statistics, and the chi square goodness of fit test using WINSTEP PCM analysis and SPSS. The major findings of the study indicated that: The standard error of measurement (SEM) of items of WAEC and NECO practical physics in 2011 and 2012 were very low- below 0.18 for all items. The fit statistic indicated that nearly all the items of both exams NECO and WAEC were valid and thus sufficiently demonstrated unidimensionality; The item difficulty estimates (b) for both examinations for the two years studied showed that all the items have difficulty estimates that range between -1.53 to +1.94 which show that their difficulty are moderate for all items. All the four different tests that constituted the instrument had very high proportion of their item fit to PCM with all the four parts having 0.92 proportion of fit. Other findings of the study include; There was significant difference in NECO 2011and NECO 2012, SEM. There was no significant difference between WAEC 2011 and WAEC 2012; NECO 2011 and WAEC 2011; NECO 2012 and WAEC 2012, SEM; NECO 2011 and NECO 2012; WAEC 2011 and WAEC 2012; NECO 2011 and WAEC 2011; NECO 2012and WAEC 2012 fit (validity) analysis; and in the difficulty estimates of NECO 2011 and NECO 2012; WAEC 2011 and WAEC 2012; NECO 2011 and WAEC 2011; NECO 2012 and WAEC 2012 tests. Based on the close resemblance of the psychometric qualities of these two examination bodies as revealed by these findings it is recommended that the confidence and recognition accorded to these two examination bodies by the public and educational institutions continues to be the same.



Background of the Study

Societal development and breakthrough in any nation are predicated on education sector of such a nation. New researches prove the long held expectation that human capital formation (the population education) plays a significant role in country’s economic development. Quality education leads not only to higher individual output but is also a necessary precondition for long term economic growth. Rigorous analysis of data provides policy makers with proof that education is a necessary precondition for long term economic development.

It is for the above reason that Nigeria in her National Policy in Education adopted education as an instrument “par excellence” for effecting national development and harnessing the potentials of the citizens (Federal Republic of Nigeria, FRN 2008). Akindogu and Bamjoko (2010) pointed out that the country’s vision is for a complete transformation of all aspects of the nations life over time and that education should be able to effect inter and intra generational transmission of our cherished heritages and life inventions and should reposition Nigeria global status in science and technology in all spheres of life.

While commenting on the role of education in national development, Blogspot (2009) noted that education is a milestone for all types of development and provides all knowledge to do any work in a systematic way. According to this author, with education any country can develop her economy and society, develop the personality of youths of the nation; make the citizens more productive by providing large number of skills to make them self reliant.

The major challenge for education in the twenty first century for our country Nigeria according to Maduagwu (2008) is designing an educational system that will be stable and global in outlook, and maintaining high standard of education.