No, because they were only interested in the question of when are anorexics born, so it made sense to only study those.

不，因为他们只对厌食症患者是,什么时候出生的这个问题感兴趣，所以只研究这些对象是有道理的。

麻省理工公开课 - 计算机科学及编程导论课程节选

Now maybe you're right, that we could study that, in fact, more people are born in June period.

可能你说的对，调查那些没有患厌食症的人，实际上还是会发现大多数人都是6月出生的。

麻省理工公开课 - 计算机科学及编程导论课程节选

STUDENT: They only studied diagnosed anorexics.

他们只对被确诊为厌食症的人做了实验。

麻省理工公开课 - 计算机科学及编程导论课程节选

Each of whom had been diagnosed anorexic.

她们每个人都有厌食症。

麻省理工公开课 - 计算机科学及编程导论课程节选