Chapter 5.1, Problem 37E

a)

To determine

To find population and sample.

Answer to Problem 37E

Population is national adults and sample is 178,545 people.

Explanation of Solution

Given:

A Gallup poll asked whether people experienced stress "a lot of the day yesterday." Forty percent said they did. Gallup's report said, "Results are based on telephone interviews with 178,545 national adults, aged 18 and older.

First need to understand about sample and population.

Population: It is the set of all the possible individuals possessing the characteristic of interest in a study.

Sample: it is the subset of population on which, the actual study performed and from which, the necessary measurements are taken.

Here, population is national adults. The sample is selected 178,545 national adults of who the telephone interviews were taken.

b)

To determine

To Explain undercoverage bias.

Explanation of Solution

Given:

A Gallup poll asked whether people experienced stress "a lot of the day yesterday." Forty percent said they did. Gallup's report said, "Results are based on telephone interviews with 178,545 national adults, aged 18 and older.

The given survey is done by a telephone. Therefore, there might be a different opinion of people who don’t have telephone. Therefore, the selected sample does not be a representative of a population. This leads to be undercoverage bias.