送交者: xj 于 2005-12-01, 20:35:56:

回答: 数据如下 由 雪泥 于 2005-12-01, 20:00:33:

I am wondering if he/she did a mailed survey.

What's the response rate? What are the racial composition? gender distribution? science major distribution? College types?

Results are likely biased if the response rates differ among different groups too.

• 如内文 - 雪泥 (534 bytes) 2005-12-01, 21:04:35
  • sampling is only one step in the study - wasguru (298 bytes) 2005-12-02, 00:30:10
  • I guess the sample size is not big too - xj (489 bytes) 2005-12-01, 22:08:04

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