来自《耶鲁大学开放课程：有关食物的心理学、生物学和政治学 第3集 第3集》

• 
  
  were they fried or baked,
  它们是炸的还是烤的
• 
  
  or eaten in some other form?
  或者以其他方式食用
• 
  
  Now you can begin to see the kinds of errors
  现在你就可以明白各种误差
• 
  
  that this method might produce because people forget,
  是由人们的遗忘而产生的
• 
  
  they can't remember exactly how much they ate of things,
  他们无法准确记得吃了多少东西
• 
  
  or they may not be willing to disclose everything they ate.
  他们不会透露所有自己吃的东西
• 
  
  So for all these reasons
  以上种种原因
• 
  
  there's some error in this kind of thing.
  造成了研究中的误差
• 
  
  A food frequency--by the way,
  食物摄取频率 顺便说下
• 
  
  you also have the issue
  还有一个问题
• 
  
  of whether the particular twenty-four hours
  就是在选取的24小时里
• 
  
  that a person is interviewed
  测试者