如何利用Java编写在线考试系统的试卷质量评估

public class ExamEvaluation {
    // 计算试题的难易程度
    public double calculateDifficulty(Question question) {
        // 根据试题的难度系数计算难度
        // 假设难度系数在0-1之间，0代表最简单，1代表最难
        return question.getCoefficient();
    }

    // 计算试题的区分度
    public double calculateDiscrimination(Question question, List<StudentAnswer> studentAnswers) {
        // 计算每个选项的选择人数
        Map<String, Integer> optionCount = new HashMap<>();
        for (StudentAnswer answer : studentAnswers) {
            String option = answer.getOption();
            optionCount.put(option, optionCount.getOrDefault(option, 0) + 1);
        }
        
        // 计算正确选项的选择人数
        int correctOptionCount = optionCount.getOrDefault(question.getCorrectOption(), 0);
        
        // 计算区分度
        double discrimination = (double) correctOptionCount / studentAnswers.size();

        return discrimination;
    }
    
    // 计算试题的选择性
    public double calculateSelectivity(Question question, List<StudentAnswer> studentAnswers) {
        // 计算每个选项的选择人数
        Map<String, Integer> optionCount = new HashMap<>();
        for (StudentAnswer answer : studentAnswers) {
            String option = answer.getOption();
            optionCount.put(option, optionCount.getOrDefault(option, 0) + 1);
        }
        
        // 计算每个选项的选择率
        Map<String, Double> optionSelectivity = new HashMap<>();
        int totalStudentCount = studentAnswers.size();
        for (String option : question.getOptions()) {
            int optionCount = optionCount.getOrDefault(option, 0);
            double selectivity = (double) optionCount / totalStudentCount;
            optionSelectivity.put(option, selectivity);
        }
        
        // 计算选择性
        double selectivity = 1.0 - Collections.max(optionSelectivity.values());

        return selectivity;
    }
}