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Chapter 4: Q 10. (page 226)

A sampling at the mall You have probably seen the mall interviewer, approaching people passing by with a clipboard in hand. Explain why even a large sample of mall shoppers would not provide a trustworthy estimate of the current unemployment rate.

Short Answer

Expert verified

Because the unemployed have more time off than those who reside in the mall, the unemployment rate will most likely be greater.

Step by step solution

01

Given information

Given the sample size, n

Because the provincial health-care system is meeting its objectives, the Ministry of Health conducted the Ontario Health Survey.

02

Concept

A simple random sample (SRS) of size n is made up of n people chosen from the population with an equal chance of being the sample that is actually chosen.

03

Explanation

A big sample of mall customers would not produce a reliable estimate of the current unemployment rate because it is easy to find a large number of people in a mall, hence this is a convenience sample. Because the unemployed have more time to spend at the mall than those who are employed, a large sample of mall visitors would not yield a reliable estimate of the present unemployment rate.

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