JsPsych按准确率标准循环试次陷入无限循环问题求助

我是JsPsych新手，正在开发一个简单的数学测验任务，需求是随机展示数学题目，用户答对10题后任务结束。目前代码实现了随机选题和循环功能，但陷入无限循环，不确定错误出在以下哪一处：

• 正确答案定义位置
• 答对次数计数逻辑
• 题目循环逻辑

附上两次尝试的代码，麻烦帮忙排查。

第一次尝试代码 #

<!DOCTYPE html>
<html>
  <head> <!-- all preloads go into head -->
    <title>Math Quiz</title>
    <!-- any plugins go here-->
    <script src="jspsych/dist/jspsych.js"></script>
    <script src = "jspsych/dist/plugin-survey-text.js"></script>
    <link href="jspsych/dist/jspsych.css" rel="stylesheet" type="text/css" />
  </head>
  <body> <!-- all script for tasks go into body-->
    <script> 
    
    var jsPsych = initJsPsych();

    var timeline = [];

// create a randomly selected math problem prompt and define correct answer
var test = {
    type: jsPsychSurveyText,
    questions: [
        {
            prompt: function() {
                var MathQuest = [

                '2+2', '3+7', 'How many weeks in a year?'

                ];

                var mathProblems = jsPsych.randomization.sampleWithReplacement(MathQuest, 1)[0];
                return mathProblems;
            },
            name: 'resp',
        }
    ],
    post_trial_gap: 500,
    on_finish: function(data) {
        var correctResponses = {

        '2+2' : '4',
        '3+7' : '10',
        'How many weeks in a year?' : '52'
        };

        var response = data.response;

        if (correctResponses[data.prompt] === response) {

            data.correct = true;

        } else {

            data.correct = false;

        }
    }
}; // end test trial

 // Create a loop node for the test with accuracy criteria:
 var correctCount = 0; // Counter for correct responses

      var loopNode = {
        timeline: [test],
        loop_function: function(data) {
          // Check if the loop should continue based on the number of correct responses
          if (correctCount < 10) {
            if (data.values()[0].correct) {
              correctCount++;
            }
            return true; // Continue the loop
          } else {
            return false; // End the loop
          }
          console.log("Correct Count: " + correctCount);
        },
      };

    jsPsych.run([loopNode]);

    </script>
    </body>
    </html>

第二次尝试代码 #

<!DOCTYPE html>
<html>
  <head> <!-- all preloads go into head -->
    <title>Math Quiz Take 2</title>
    <!-- any plugins go here-->
    <script src="jspsych/dist/jspsych.js"></script>
    <script src = "jspsych/dist/plugin-survey-text.js"></script>
    <link href="jspsych/dist/jspsych.css" rel="stylesheet" type="text/css" />
  </head>
  <body> <!-- all script for tasks go into body-->
    <script> 

var jsPsych = initJsPsych();

var timeline = [];

var mathQuestions = [
  {math: '2+2 = ?', correct: '4'},
  {math: '2x3 = ?', correct: '6'},
  {math: '5x7 = ?', correct: '35'}
];

var test = {
  type: jsPsychSurveyText,
  questions: [
    {
      prompt: jsPsych.timelineVariable('math'), 
      name: 'resp'
    }
  ],
        on_finish: function(data) {
                  data.correct=jsPsych.timelineVariable('correct');
                  var acc = 0;
                  var response = data.response.resp;
            if (response == data.correct){
                acc++;
            }
          }
};

var mathQuestionProcedure = {
  timeline: [test],
  timeline_variables: mathQuestions,
  loop_function: function(data) {
    if (acc < 2) {
            return true; //go to criteria
        } else {
            return false; //end loop
        }
  }
}
timeline.push(mathQuestionProcedure);

jsPsych.run([mathQuestionProcedure])

</script>
</body>
</html>

问题排查与修正 #

第一次尝试的核心问题 #

1. data.prompt无法获取当前题目文本：
   你在prompt里用了函数动态生成题目，但JsPsych不会把函数的返回值存储到data.prompt中，所以correctResponses[data.prompt]永远找不到匹配项，data.correct一直是false，导致correctCount永远不会增加，循环永远停不下来。
2. console.log位置无效：
   它被放在return语句之后，永远不会执行，没法调试计数情况。

修正方案：
在生成题目时，把当前题目文本主动存入数据中，然后在on_finish里用这个存储的字段判断答案：

prompt: function() {
    var MathQuest = ['2+2', '3+7', 'How many weeks in a year?'];
    var mathProblems = jsPsych.randomization.sampleWithReplacement(MathQuest, 1)[0];
    // 把当前题目存入数据
    jsPsych.data.addData({current_question: mathProblems});
    return mathProblems;
},

然后在on_finish里修改判断逻辑：

on_finish: function(data) {
    var correctResponses = {
        '2+2' : '4',
        '3+7' : '10',
        'How many weeks in a year?' : '52'
    };
    // 用存储的current_question匹配正确答案
    var response = data.response.resp; // survey-text插件的response是对象，要取name对应的字段
    data.correct = (correctResponses[data.current_question] === response);
}

同时把console.log移到return之前，确保能输出计数。

第二次尝试的核心问题 #

1. acc变量作用域错误：
   acc定义在on_finish函数内部，每次触发on_finish都会重置为0，而且loop_function里访问的acc是全局变量，根本没被赋值过（始终是undefined），undefined < 2永远为真，循环停不下来。
2. timelineVariable在on_finish中无法正确获取值：
   on_finish执行时，timeline变量的上下文已经结束，应该用data.timeline_variables.correct来获取当前题目的正确答案。

修正方案：

• 把acc定义在全局作用域，作为累计计数器；
• 修改on_finish里的逻辑，正确判断答案并更新计数器；
• 在loop_function里根据计数器判断是否停止循环：

// 全局定义计数器
var correctCount = 0;

var test = {
  type: jsPsychSurveyText,
  questions: [
    {
      prompt: jsPsych.timelineVariable('math'), 
      name: 'resp'
    }
  ],
  on_finish: function(data) {
    // 获取当前题目的正确答案
    var correctAnswer = data.timeline_variables.correct;
    var userResponse = data.response.resp;
    // 判断是否正确，并存入数据
    data.correct = (userResponse === correctAnswer);
    // 如果正确，更新计数器
    if(data.correct){
        correctCount++;
    }
  }
};

var mathQuestionProcedure = {
  timeline: [test],
  timeline_variables: mathQuestions,
  // 随机选题，满足需求
  randomize_order: true,
  loop_function: function(data) {
    // 答对2题就停止（可改成10）
    return correctCount < 2;
  }
}

内容的提问来源于stack exchange，提问作者mbeasle2