Suppose you wanted to select a representative random sample

Suppose you wanted to select a representative random sample of students on your campus for a face-to-face interview. How would you do this? How would you ensure that your sample was random as well as representative of the student population?

Solution

A random sample is one such that each item in the population from which the sample is drawn has an equal probability of being included in the sample .  The reason why this is important is that a random sample provides an unbiased estimate of the characteristics of the population.  The sample can then be used to “represent” the population.  Put another way, if 60 percent of a random sample of voters favor candidate X then, although it would be impractical to interview all voters, our best guess is that 60 percent of all voters also favor candidate X

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