Historical data indicate that the standard deviation of a process is 6.7.a. A recent sample of size 28 produced a variance of 67.2. Test to determine if the variance has increased using a significance level of 0.05.b. A recent sample of size 9 produced a variance of 7.65. Test to determine if the variance has decreased using a significance level of 0.025.c. A recent sample of size 18 produced a variance of 63.7. Test to determine if the variance has changed using a significance level of 0.10.a. Formulate the null and alternative hypotheses. Select the correct choice below and fill in the answer boxes to complete your choice.(Type integers or decimals. Do not round.)O A. Ho: o2 sO B. Ho: o 2HA: o2HA: o <O C. Ho: o2 =O D. Ho: o2 +Construct the rejection region and define the decision rule.(Round to two decimal places as needed.)O A. Ifx? < xổ 95O B. If x? > xổ 025 = I, or if x? < xổ.975 =OC. Ifx? > xổ.o5reject the null hypothesis.reject the null hypothesis.reject the null hypothesis.Compute the test statistic.(Round to two decimal places as needed.)Reach a decision and draw a conclusion.Because x isV the rejection region,v the null hypothesis andV that the variance of the process hasb. Formulate the null and alternative hypotheses.(Type integers or decimals. Do not round.)O A.Ноo2 =OB.Ho: o2HA: 0?HA: o? <Oc.НоO D. Ho: o? +HA: o2>HA: o? =Construct the rejection region and define the decision rule.(Round to two decimal places as needed.)O A. If x? > xổ.025O B. If x > xổ.0125OC. Ifx < x6.975reject the null hypothesis., or if x? < xo.9875reject the null hypothesis.reject the null hypothesis. Compute the test statistic.(Round to two decimal places as needed.)Reach a decision and draw a conclusion.Because x isv the rejection region,v the null hypothesis andV that the variance of the process hasc. Formulate the null and alternative hypotheses.(Type integers or decimals. Do not round.)O A. Ho: o2+OB.Họ:HAo2 =HA: o?>O C. Ho: o2 =OD.НоНАConstruct the rejection region and define the decision rule.(Round to two decimal places as needed.)O A. Ifx? > xổ 10O B. If x? > x6.05reject the null hypothesis.or if x? < x6 95 -, reject the null hypothesis.%3D0.95OC. Ifx?

Given, σ = 6.7 Here we use chi-square test. The formulafor chi-square test statistics is: χ2 = (n-1)…

Historical data indicate that the standard deviation of a process is 6.7. a. A recent sample of size 28 produced a variance of 67.2. Test to determine if the variance has increased using a significance level of 0.05. b. A recent sample of size 9 produced a variance of 7.65. Test to determine if the variance has decreased using a significance level of 0.025. c. A recent sample of size 18 produced a variance of 63.7. Test to determine if the variance has changed using a significance level of 0.10.

Historical data indicate that the standard deviation of a process is 6.7. a. A recent sample of size 28 produced a variance of 67.2. Test to determine if the variance has increased using a significance level of 0.05. b. A recent sample of size 9 produced a variance of 7.65. Test to determine if the variance has decreased using a significance level of 0.025. c. A recent sample of size 18 produced a variance of 63.7. Test to determine if the variance has changed using a significance level of 0.10.

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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