Chapter 12, Problem 18STP

a.

To determine

To state: the sample.

Answer to Problem 18STP

The sample is the voters.

Explanation of Solution

Given information:

Committee randomly calls $250$ houses and ask codes that are inside the voting district and the opinions of registered voters. Committee determines that $71\%\left(\pm 2.5\%\right)$ of voting population support the issue.

the committee randomly calls to the houses so the sample is the voters where the committee calls.

b.

To determine

To state: the population.

Answer to Problem 18STP

The population is the voters of the houses.

Explanation of Solution

Given information:

Committee randomly calls $250$ houses and ask codes that are inside the voting district and the opinions of registered voters. Committee determines that $71\%\left(\pm 2.5\%\right)$ of voting population support the issue.

the committee randomly calls to the houses so the population is the people of voters of the houses.

c.

To determine

To state: the method of data collection used by committee.

Answer to Problem 18STP

The data collection method is survey.

Explanation of Solution

Given information:

Committee randomly calls $250$ houses and ask codes that are inside the voting district and the opinions of registered voters. Committee determines that $71\%\left(\pm 2.5\%\right)$ of voting population support the issue.

the committee randomly calls to the houses and get the data from the voters,

So the data collection method is a suvey.

d.

To determine

To state: that the sample is biased or unbiased.

Answer to Problem 18STP

The sample is unbiased.

Explanation of Solution

Given information:

Committee randomly calls $250$ houses and ask codes that are inside the voting district and the opinions of registered voters. Committee determines that $71\%\left(\pm 2.5\%\right)$ of voting population support the issue.

the committee randomly calls to the houses and here committee does not use any specific are but with the result of these voters opinion they decided the result so the sample is unbiased.

e.

To determine

To state: that the sample is simple, stratified or systematic.

Answer to Problem 18STP

The sample is simple.

Explanation of Solution

Given information:

Committee randomly calls $250$ houses and ask codes that are inside the voting district and the opinions of registered voters. Committee determines that $71\%\left(\pm 2.5\%\right)$ of voting population support the issue.

the committee randomly calls to the houses and here committee does not use any specific are but with the result of these voters opinion they decided the result so the sample is unbiased and simple.