Rungson Chomeya2011-02-202011-02-202011-01-242011-01-24Journal of Humanities and Social Sciences; Volume 28 Number 1Jan-Mar 2009; 102-110http://imsear.searo.who.int/handle/123456789/130736The main purposes of this research were (1) to study the quality evaluation psychology testLikertûs scale 5 points and 6 points (attitude test, locus of control test and achievement motive test)focusing on construct validity, discrimination and reliability, (2) to compare the study for quality psychologytest between Likertûs scale 5 points and 6 points , and (3) to compare the study for personal decisionmaking level between Likertûs scale 5 points and 6 points. The subjects were 180 (60 for each test)undergraduate students from Mahasarakham University who were selected by purposive sampling. Theresearch tools were as follows: (i) attitude test, (ii) locus of control test and (iii) achievement motive testcomprised of measurement patterns developed for different variables. Means, Standard Deviation,Factors Analysis, Alpha Coefficient and t-test were used for data analysis.The research revealed (1) the higher component and Initial Eigenvalues cumulative percent ofpsychology test Likertûs scale 5 points and 6 points but psychology test Likertûs scale 6 points had ahigher trend of discrimination and reliability than Likertûs scale 5 points, (2) the comparison wasconstruct validity, discrimination and reliability among Likertûs scale 5 points and 6 points. It was founddifferent reliability at .05 level on achievement motive test only, and (3) the comparison of personaldecision making level psychology test between Likertûs scale 5 points and 6 points was different at .05level.en-USJournal of Humanities and Social SciencesArticles