EXAMPLE 6 TV ratings

Market research is designed to discover what consumers want and what products they use. One example of market research is the television-rating service of Nielsen Media Research. The Nielsen ratings influence how much advertisers will pay to sponsor a program and whether or not the program stays on the air. For the Nielsen national TV ratings:

Population: The more than 116 million U.S. households that have a television set.

Sample: About 25,000 households that agree to use a “people meter” to record the TV viewing of all people in the household.

The variables recorded include the number of people in the household and their age and sex, whether the TV set is in use at each time period, and, if so, what program is being watched and who is watching it.