A Study On Applying IRT Into Prersonality Tests

As personality tests are applied more broadly in practical field , it plays a more important role. Most studies on personality tests analyzed and explained on the basis of the Classical Test Theory(CTT). This article applies Item Response Theory(IRT) to personality tests to score and explain them. In the Empirical Study One, score patterns of the two test theories are analyesed, the differences of some subsjects' scores are compared, and finally the cause is explored. The results shows that the scores in IRT take the performance of items into account and the same scores is less simliar, more accourate, less misclassification than those in CTT. In the Empirical Study Two, measurement errors of the two test theories are compared. CTT has only one measurement error in the test. However, IRT brings into information function ,which can more accurately evaluate the quality of items and test and the ability of examinees than CTT does, so it has more strong guidance in test. At the same time, IRT also offers the test information function to make the maxium information and measure errors known more conveniently in the certain trait level, which provides the theortical and practical foundation for the personality test constructed according to test accuracy.