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Chapter 10: Q. T10.1 (page 697)

A study of road rage asked separate random samples of 596men and 523 women

about their behavior while driving. Based on their answers, each respondent was

assigned a road rage score on a scale of 0 to 20. Are the conditions for performing a

two-sample t test satisfied?

a. Maybe; we have independent random samples, but we should look at the data to

check Normality.

b. No; road rage scores on a scale from 0 to 20 can鈥檛 be Normal.

c. No; we don鈥檛 know the population standard deviations.

d. Yes; the large sample sizes guarantee that the corresponding population

distributions will be Normal.

e. Yes; we have two independent random samples and large sample sizes.

Short Answer

Expert verified

The correct answer is:

e. Yes; we have two independent random samples and large sample sizes.

Step by step solution

01

Given information

We are given separate samples of 596men and 523women about their behavior while driving.

Conditions for performing a two-sample t-test: Random, Normal and Independent.

02

Explanation

Random: I'm satisfied because the samples were supplied to me at random.

Normal: Because each sample has a sample size of at least 30, it can be presumed to be satisfied.

Independent: Satisfied. Because the random samples were given to be separate, they are now independent. Furthermore, the sample sizes are less than 10%of the whole population.

Because all three conditions have been met, answer (e) is correct.

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