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Chapter 10: Q.1 (page 664)

A study of road rage asked separate random samples of 596men and 523women about their behavior while driving. Based on their answers, each re-spondent was assigned a road rage score on a scale of 0to 20. Are the conditions for performing a two-sample t test satisfied?

a) Maybe; we have independent random samples, but we need to look at the data to check Normality.

(b) No; road rage scores in a range between 0 and 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

A study of road rage asked separate random samples of 596 men and 523 women about their behavior while driving.

02

Explanation

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

Random: Satisfied, because the samples have been given to be random samples.

Normal: Can be assumed to be satisfied, because the sample size of each sample is at least 30.

Independent: Satisfied. The random samples have been given to be separate and thus are independent. Moreover, the sample sizes are less than 10% of the population size.

Thus all three conditions have been satisfied and thus answer (e) is correct.

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