(a) Compute the 90% confidence interval estimate of the population variance.A confidence interval for the population variance a? will have the following form where n is the sample sizeand s? is the sample variance. The x? values correspond to a chi-square distribution with n - 1 degrees offreedom where " and 1 -.aare the upper tail areas.2(n - 1)s?2X al2(n - 1)s?2X1- a/2Recall that the value of alpha is found by setting the confidence level equal to (1 - a) and solving for a. A90% confidence interval is to be found. Expressing 90% as a probability gives 0.90, so we have 1 - a = 0.90.Therefore, a = 0.10, so2and 1 -2=The sample size is n = 20, so the degrees of freedom is n - 1 =SubmitSkip (you cannot come back)

alpha/2 = 0.10/2 = 0.05 1-alpha/2 = 1-0.05 = 0.95 DF = n-1 = 20-1 = 19

(a) Compute the 90% confidence interval estimate of the population variance. A confidence interval for the population variance o? will have the following form where n is the sample size and s? is the sample variance. The x? values correspond to a chi-square distribution with n - 1 degrees of freedom where and 1 - are the upper tail areas. (n – 1)s² x1- a/2 (n – 1)s2 Recall that the value of alpha is found by setting the confidence level equal to (1 – a) and solving for a. A 90% confidence interval is to be found. Expressing 90% as a probability gives 0.90, so we have 1 - a = 0.90. Therefore, a = 0.10, so 4 - ] and 1 - 4 - 2 The sample size is n = 20, so the degrees of freedom is n - 1 =

(a) Compute the 90% confidence interval estimate of the population variance. A confidence interval for the population variance o? will have the following form where n is the sample size and s? is the sample variance. The x? values correspond to a chi-square distribution with n - 1 degrees of freedom where and 1 - are the upper tail areas. (n – 1)s² x1- a/2 (n – 1)s2 Recall that the value of alpha is found by setting the confidence level equal to (1 – a) and solving for a. A 90% confidence interval is to be found. Expressing 90% as a probability gives 0.90, so we have 1 - a = 0.90. Therefore, a = 0.10, so 4 - ] and 1 - 4 - 2 The sample size is n = 20, so the degrees of freedom is n - 1 =

MATLAB: An Introduction with Applications

6th Edition

ISBN:9781119256830

Author:Amos Gilat

Publisher:Amos Gilat

Chapter1: Starting With Matlab

Section: Chapter Questions

Problem 1P

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6
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