The Research Of Intelligent Test Paper Auto-generation Based On An Improved Genetic Algorithm

With the development of computer based education, computer examination system as an important component of computer managed instruction gets more and more attention. In the examination system, test paper auto-generation is an important factor in evaluating the system and decides wether the system can effectively test students' truth levels. So the study of test paper generation algorithm is a significant topic of computer based education. Existing test paper generation algorithms have some defects, such as low success ratio, costing long time and poor quality of test paper. Aimed at these defects, the intelligent test paper auto-generation algorithm based on genetic algorithm is researched in this paper.Firstly, the basic theories and principles of test paper generation are expounded and the constraint conditions are summarized. Based on them, a mathematical model of test paper generation is established. Secondly, aimed at genetic algorithm's shortage, the reason why precocious convergence is easy to occur, usual solutions to precocious convergence and measurements of population diversity are introduced. An adaptive algorithm based on evaluration of population diversity are presented. In the improved algorithm, there are two changed aspects. One is the way to adjust the probability of genetic operators and the other is the replacement strategy. The validity of the improved algorithm is proved by simulation tests. The tests results show that the improved algorithm can improve global optimization ability and the convergence speed. Finally, the improved algorithm is used to solve test paper generation problem. According to the characters of test paper genetation problem, a coding method named paragraphed interger coding is used. Due to the coding strategy, crossover and mutation operator are designed. The simulation test indicates that the intellegent test paper auto-genetation algorithm based on improved genetic algorithm can satisfy the needs for actual examinations, the speed is faster and the quality of test paper is better.