关键词: 随机洗牌, 轮转, 策略集

Abstract:  Research on generating test paper in electronic examination system (E-Exam System) remains a comprehensive problem in teaching and examination reform of colleges and universities because it requires high efficiency, randomness and balance in algorithm, meanwhile the extracting test paper combination should meet the users’ custom sets strategy. This paper presents a strategy-sets-based reduce range of algorithm’s parameters, which firstly applies a random shuffle algorithm towards test papers and the process of generating test papers to guarantee the randomness of abstracting test questions; then prunes the value domain ahead of time by using strategy sets and reduces the value range of the current target set to ensure fast return of algorithm; finally rotates the abstracting targets with strategy sets to realize test paper adjustment based on strategies. After the test of abstracting 1000 test papers from a 100000 questions Test Bank, this algorithm shows the following features: it can abstract item quantity accord to the goal within very short time (127 s); algorithm efficiency and the number of test paper composition show a variation trend of quadratic function; it has less sensitiveness towards the number of questions in test bank so this algorithm is suitable for a relatively large test bank.

Key words: random shuffling algorithm, rotate, strategy set