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Chapter 9: Q 99. (page 610)

Sampling shoppers A marketing consultant observes 50 consecutive shoppers at a supermarket, recording how much each shopper spends in the store. Explain why it would not be wise to use these data to carry out a significant test about the mean amount spent by all shoppers at this supermarket.

Short Answer

Expert verified

The sample is a convenience sample.

Step by step solution

01

Given information

Consecutive shoppers: 50

02

Calculation

Because the shoppers were "conveniently" picked as 50 consecutive shoppers, the sample is a convenience sample. These customers shop on the same day of the week and at the same time of day, implying that we may be excluding a portion of the population.

As a result, the sample is not representative of the entire population.

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Most popular questions from this chapter

Reporting cheating What proportion of students are willing to report cheating by other students? A student project put this question to an SRS of 172 undergraduates at a large university: “You witness two students cheating on a quiz. Do you go to the professor?” The Minitab output shows the results of a significance test and a 95% confidence interval based on the survey data.13

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