**QUESTION**

A market researcher chooses at random from women entering a large upscale department store. One outcome of the study is a 95%95% confidence interval for the mean of “the highest price you would pay for a handbag.”

(a) Why does this confidence interval not give useful information about the population of all women?

A convenience sample was used.

A stratified sample was used.

A voluntary response sample was used.

A simple random sample was used.

(b) Explain why this confidence interval may give useful information about the population of women who shop at large upscale department stores.

This confidence interval may give useful information about the population of women who shop at large upscale department stores because the required sample, as stated, is a convenience sample, and so is the chosen sample.

This confidence interval may give useful information about the population of women who shop at large upscale department stores because the mall is an SRS of all large upscale department stores.

This confidence interval may give useful information about the population of women who shop at large upscale department stores because there are not too many women in one department store, even though it is large, hence it is possible to ask all the women in the store, and obtain an accurate answer.

This confidence interval may give useful information about the population of women who shop at large upscale department stores because the sample is random. The sample is likely to represent the population of all women who shop at large upscale department stores.