除了样本误差外，全国性的公众意见的调查操作上的困难也会导致误差。

In addition to sampling error, the practical difficulties of conducting any survey of public opinion may introduce other sources of error into the poll.

youdao

研究结果是基于1990年后的一个全国性的男性女性测验样本，这些样本具备相当的同质性。

Said the study builds upon research in the 1990s that tested similar patterns in a national sample of working women and men.

youdao

我们用1992年至2001年全国性的患者作为样本，确定其初始诊断、手术方法和相关的院内并发症和死亡率。

Using the Nationwide Inpatient Sample, we determined the primary diagnoses, surgical procedures, and associated in-hospital complications and mortality from 1992 to 2001.

youdao

And you know, even if people are doing these things anonymously, or they're part of a big national sample where they're one of thousands and thousands of subjects, people don't necessarily like to say that they're doing something that they don't think they should be doing.

你知道,即使人们参加的是匿名调查,或他们是全国性样本中的一员,他们是那数以千计万计总体中的一员,人们似乎也没有必要说出,他们做的一些,自认为不应该做的事情

耶鲁公开课 - 关于食物的心理学、生物学和政治学课程节选