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The Practice of Statistics for AP
Found in: Page 592
The Practice of Statistics for AP

The Practice of Statistics for AP

Book edition 4th
Author(s) David Moore,Daren Starnes,Dan Yates
Pages 809 pages
ISBN 9781319113339

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Short Answer

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 significance test about the mean amount spent by all shoppers at this supermarket.

Convenience sample.

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Step by Step Solution

TABLE OF CONTENTS :
TABLE OF CONTENTS

Step-1 Given Information

Given in the question that, A marketing consultant observes 50 consecutive shoppers at a supermarket, we have to Explain why it would not be wise to use these data to carry out a significance test about the mean amount spent by all shoppers at this supermarket.

Step-2 Explanation

A convenient sample is a non-probability sampling method in which the sample is taken from a group of people who are easy to touch or encounter. A convenience survey, for example, would entail standing outside a mall or a grocery store and asking customers to complete questionnaires. This kind of sampling is also known as grab sampling or availability sampling. The poll is a choice study, as the shoppers were chosen because they were "conveniently" consecutive.

There would also be shoppers who went shopping on the same day of the week and at the same time, implying that a segment of the population was left out.

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