The Development Of Computerized Adaptive Test Of Mathematical Ability For Junior Students

Multidimensional Item Response Theory,Cognitive Diagnosis and Computerized Adaptive Test are three important research directions in the future.Based on Item Response Theory and taking computer as medium,the computerized adaptive test chooses the item for students according to the updated ability estimation to customize the test for every student,thus simultaneously improves the test efficiency and accuracy.However,there are seldom self-development computerized adaptive test,so the present study focuses on the mathematical ability evaluate in compulsory education,devoting to developing a computerized adaptive test which can provide instructions for studying and teaching in practice.The study was conducted as the following five parts:First of all,the present study defines the concept of computerized adaptive test and mathematical ability based on the former study,especially the structure of the later,which is used to establish the item pool.Then the author clarifies the purpose and the significance of the study,listing the whole procedure of the research.Secondly,introducing the developmental history and characteristics of Classical Test and Item Response Theory which the study are based on and emphasizing the advantages of item response theory.We make up the items according to the guidance of CTT while use the method provided by IRT to estimate parameters and analyze items.Thirdly,establishing the item pool should follow several steps:first,organize items with different difficulty levels to develop a traditional paper and pencil test,in total 500 items;Then,adopt anchor item design to reconstruct the test to be 20 subsidiary test and conduct the tests among 4443 junior students to collect information for estimation of parameters of the items.Next,use statistical methods to test the model and item fitness,then select the appropriate model to calculate three parameters for item:difficulty,discrimination and guessing parameters.Finally,448 well-developed items are chosen to establish the item pool.In the fourth part,introducing how to design and realize the computerized test system.The system was divided to two modules:management module and test module.In the former,the admin can adjust the system function,browse student information and alter item details.In the test module,student will complete the entire test process from log-in to grades feedback.Also,the author have selected the appropriate techniques for the next four procedures:1)ability estimation:maximum likelihood method;2)item selection strategies:STR_b combining with content balancing to strengthen the security of the system;3)ending rule:the information amount arrive above 16 or the test time longer than 40minites;4)result transformation:transfer the theta which located between-3 to 3 to pai which located between 0 and 1 to be more meaningful for examinees.The fifth part is about the analysis of the test administration results.The author test and adjust the system until there is no visible questions and administer the test among junior students varying form Grade 7 to Grade 9,to examine the security of the item pool and the reliability and validity of the test.Finally,the results shows that the system works well to manage and conduct the test.Also,there proves to be a relatively high discrimination for students of different ability levels and a balance item exposure rate which promising for higher security.