Application Of IRT Multicategory Scoring Item

Item Response Theory (IRT) is a completely new test theory developed after overcoming the various limitations of the Classic Test Theory (CTT). The development of Item response theory is firstly based on the latent trait theory. Its main content is to reveal to test the relationships between the response behavior of the tested on the test item and the latent trait of the tested in the test.Comparing to the CTT, the item response theory has obvious advantages. The item parameter it used (such as difficulty, distinction level and guessing index) is a kind of index which not affected by samples. Access to these parameters will not change with the change of the varying samples tested. Meanwhile, the estimation of the capability of the tested will not change with the change of different exam questions. Due to those mentioned advantages of Item Response Theory (IRT), it has been widely used in the psychology and tests, especially the application of extensive multi-level score model in the proficiency test score model. This thesis will explore the application of multi-level score model under the framework of IRT to provide the reference materials for the assessment quality of test questions and the building of test questions bank.