Problem

Researchers conducted an experiment to test the effects of alcohol. Errors were recorded in a test of visual and motor skills for a treatment group of 22 people who drank ethanol and another group of 22 people given a placebo. The errors for the treatment group have a standard deviation of 2.40 , and the errors for the placebo group have a standard deviation of 0.87 . Assume that the two populations are normally distributed. Use a 0.05 significance level to test the claim that both groups have the same amount of variation among the errors.

Let sample 1 be the sample with the larger sample variance, and let sample 2 be the sample with the smaller sample variance. What are the null and alternative hypotheses?
A. H0:σ12=σ22
B.
H1:σ12<σ22
H0:σ12=σ22H1:σ12σ22
 C. H0:σ12=σ22H1:σ12>σ22
D.
H0:σ12σ22H1:σ12=σ22

Identify the test statistic.
7.61 (Round to two decimal places as needed.)

Use technology to identify the P-value.
(Round to three decimal places as needed.)

Answer

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Answer

Calculate the P-value using the chi-square distribution with degrees of freedom equal to the sample size minus 1. The P-value is the probability of observing a test statistic as extreme as the one calculated, assuming the null hypothesis is true. The specific value of the P-value is not provided in the question.

Steps

Step 1 :Define the null and alternative hypotheses as follows: \n\nH0:σ12=σ22\H1:σ12σ22

Step 2 :Calculate the test statistic. The test statistic is 7.61.

Step 3 :Calculate the P-value using the chi-square distribution with degrees of freedom equal to the sample size minus 1. The P-value is the probability of observing a test statistic as extreme as the one calculated, assuming the null hypothesis is true. The specific value of the P-value is not provided in the question.

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