MATLAB: An Introduction with Applications
6th Edition
ISBN: 9781119256830
Author: Amos Gilat
Publisher: John Wiley & Sons Inc
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Transcribed Image Text: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 23 people who drank ethanol and another group of 23 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 0.78. 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?
OA. H₂:0² = 0²/2
OB. H₂:0² = 0²/2
H₁: 0²/12 #02/22
H₁:0² > 0²/2
ỌC Họỏi cơ
OD. Ho: 0²/02/2
H₁:0² <0²
H₁:0² = 0²/2
Identify the test statistic.
(Round to two decimal places as needed.)
Use technology to identify the P-value.
(Round to three decimal places as needed.)
Transcribed Image Text:What is the conclusion for this hypothesis test?
A. Reject Ho. There is insufficient evidence to warrant rejection of the claim that both groups have the same amount of variation among the errors.
B. Fail to reject Ho. There is sufficient evidence to warrant rejection of the claim that both groups have the same amount of variation among the errors.
C. Reject Ho. There is sufficient evidence to warrant rejection of the claim that both groups have the same amount of variation among the errors.
O D. Fail to reject Hỏ. There is insufficient evidence to warrant rejection of the claim that both groups have the same amount of variation among the errors.
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