Abstract:
The purpose of this study is to develop a Verbal Reasoning Test from the Differential Aptitude Test Battery for Thai students in Matayom Suksa 3 and Matayom Suksa 5. The test is analyzed for its difficulty level and discrimination power. The reliability and validity coefficients were calculated. The percentile norms were established. The Researcher has developed the subtest : Verbal Reasoning from the DAT. The test composes of 50 items of multiple-choice type. The time-limit for the test is 30 minutes. The samples of Matayom Suksa 3 and Matayom Suksa 5 students were secured by stratified random sampling method. The results are : 1. The average of difficulty levels for the developed test for Matayom Suksa 3 and Mtayom Suksa 5 are .362 and .430, respectively. The average of discrimination power are .389 and .411 for Matayom Suksa 3 and Matayom Suksa 5. The items which meet the crireria for good items are 33 and 33 items and 30 items for Matayom Suksa 3 and Matayom Suksa 5, respectively. 2. The reliability coefficient derived from Kuder Richardson formula 20, 21 and from the Split Half Method of the Matayom Suksa 3 are .802, .783, .809 and Matayom Suksa 5 are .826, .804, .841, respectively. 3. Using Thai, English, Social Studies, Mathematics and Science as criteria of the validity indices for Matayom Suksa 3 are .4359, .4161, .3337, .3619 and the validity indices for Matayom Suksa 5 are .4948, .5180, .5154 .4080 at 99 percent of confident level, respectively 4. The percentile norms for Matayom Suksa 3 and Matayom Suksa 5 were also established.