The Development Of CTT And IRT Basing On Visual-Satial Reasoning Test

[Background] Previous study has shown that there are two basic fields in human ability:verbal ability and spatial ability. Verbal ability level reflects individual’s intelligence level, it can forecast individual’s academic and development potentials.Verbal ability can be measured through general intelligence test, reasoning test, and work memory test and etc.. Spatial ability reflects individual’s ability of operating and processing spatial images, It can forecast individual’s achievement in engineering technology.piloting, and work performance. It can be measured through mental rotating test, and blocks test, and dynamic spatial ability test and etc. these two skills are very important for the survival and development of human. But there are also many problems in these tests, such as poor discrimination among high IQs, low test accuracy, complex test operation, low ecological validity, and disability in measuring integrated ability of verbal and spatial.[Purposes] The purposes of this research is developing a spatial-reasoning scale of more superior property in order to be used in practical psychological measurement of high requirement. The test should has following advantages:It can simultaneously measure spatial ability and verbal ability, items are three-dimensional formed, with a cultural equity, simple operation, low cost, wide range effect of discrimination, efficient, high-precision, high ecological validity.[Method] In this study, based on existing research’s analysis of reasoning and spatial ability, we made a two-way item catalogue, we used three-dimensional design software rhino5.0 to design the visual spatial reasoning test items library. Pre-scale and formal scale tested a total of 1677 participants from middle and high schools, universities of Zhejiang Province and online communities. The tests are taken in forms of written tests and online tests, there are 1611 valid questionnaires. Using CTT and IRT this research analyzed items’parameters. The development of visual-spatial reasoning ability, gender differences, and answer strategies were also analyzed.[Result] CTT analysis of the scales:visual spatial reasoning test’s α=0.88.At the same time we tested 123 undergraduate students using standard raven test, the correlation between visual-spatial reasoning test scores and standard raven test scores is 0.51. we collected another 658 high school students’ academic achievement, correlations between visual-spatial reasoning test score and total academic, chinese, mathematics, english, physics and chemistry were significant positive, the highest correlation is with the physical and chemical, r=0.42. Scale has high reliability and validity; IRT analysis of Scale:through exploratory factor analysis, the first and second feature characteristic root ratio is 4.72, nearly 5, thus single-dimensional hypothesis holds, and local independence assumption is also true. All items’ discrimination are larger than 0.5, the difficulty b of all items range [-3,3], the majority of the items guess indexes are under 0.3, range[-1.1,2.4] the whole scale’s information are larger than 6, thus the scale has high measurement precision; comparing CTT and IRT parameters we found the correlation of difficulty indexes between the two theories is 0.96, while correlation of discrimination is -0.20, discrimination parameters of the two theories are essentially different; Visual spatial reasoning test score will increase with the age of the subjects and showed a gender differences, junior high school girls are superior to boys, but the difference disappears among high school students and undergraduate students. But the boys are superior to girls in efficiency, advantages peaked in high school, and this advantage has will maintained with age; boys and girls are differ in answer strategy, boys tend to value high speed, while girls tend to guarantee the correct rate.[Conclusion] All the indexes of the visual spatial reasoning scale reached the requirement of psychometrics, visual spatial reasoning ability will be improved with age among the youth, but there difference between genders, girls and boys will take different problem solving strategies in the test.[Value]Visual spatial reasoning scale can make more comprehensive forecast of the development potential. And the scale will have high value in career potential, spatial and reasoning ability, cognitive function diagnosis and education.