Chemical Adaptive Web-based Test System

The author introduces three kinds of educational test theories that are Classical Test Theory (CTT), Generalizability Theory (GT) and Item Response Theory (IRT). The hypotheses, models, parameters-guessing and information function of IRT are expatiated at length. Based on Item Response Theory, the author designed and developed web computerized adaptive test system on chemistry, and argued deeply on transforming difficulty index involved in the process of constructing the item bank. Three aspects are embodied in developing the system. First, set up the powerful item bank. The bank is on Access Database currently, and contains some tables named as item, user and calculation. Second, design wonderful web pages with Hypertext Markup Language (HTML). Third, establish suitable CGI application. The program is written with Visual Basic (VB) language, including several modules. The established research objective, enabling users all over the world to enjoy using of computerized adaptive test of chemistry through web, is thus accomplished.