Question

An advertising agency sends interviewers to a shopping mall in a major city to gather information about the effectiveness of its ads on a national television network. In one week, the interviewers chose 1,200 shoppers who took their survey. Which of the following statements describes the validity of the survey?

1. The survey is valid since the sample of shoppers was large.
2. The survey is valid since people who go to malls have money to spend on the products being advertised.
3. The survey is invalid because it did not ask shoppers about ads in other media.
4. The survey is invalid because the mall shoppers may not have been a representative sample of the public.

Answer 1

The survey is valid since the sample of shoppers was large.

Explanation:

For the given sample survey, interviewers collect the data from the 1200 shoppers which indicate that the sample size is adequate for drawing the results. Interviewers can collect the information about the sale of their products from the shoppers. It is not necessary to collect the information from the customers. Shoppers would have proper data regarding the overall sell of the products of different brands, but any particular customer cannot give proper idea about the sale of their products. So, collecting data direct from shoppers gives us more effective results for drawing conclusions. It is not necessary that shoppers would be a representative sample of the public. Also, people who go to malls have money to spend on the products do not explain the validity of this survey.