Example 1: what is wrong with this survey?
a sociologist wants to know the opinions of texas teachers about government
funding for high school sports teams. she gets a list of high school teachers in
bryan and college station, and then mails a questionnaire to 100 of the randomly
selected teachers. only 42 questionnaires are returned.
what is the population in this study?
what is the sample?
this study is biased, why? what needs to be changed?