A simple random sample of size n is drawn from a population that is known to be normally distributed. The sample variance, s“, is determined to l 12.8. Complete parts (a) through (c). (a) Construct a 90% confidence interval for o? if the sample size, n, is 20. The lower bound is (Round to two decimal places as needed.) The upper bound is . (Round to two decimal places as needed.) (b) Construct a 90% confidence interval for o² if the sample size, n, is 30. The lower bound is (Round to two decimal places as needed.) The upper bound is. (Round to two decimal places as needed.) How does increasing the sample size affect the width of the interval? The width increases The width decreases O The width does not change (c) Construct a 98% confidence interval for o2 if the sample size, n, is 20. The lower bound is . (Round to two decimal places as needed.) The upper bound is. (Round to two decimal places as needed.) Compare the results with those obtained in part (a). How does increasing the level of confidence affect the confidence interval? The width increases

A simple random sample of size n is drawn from a population that is known to be normally distributed. The sample variance, s“, is determined to l 12.8. Complete parts (a) through (c). (a) Construct a 90% confidence interval for o? if the sample size, n, is 20. The lower bound is (Round to two decimal places as needed.) The upper bound is . (Round to two decimal places as needed.) (b) Construct a 90% confidence interval for o² if the sample size, n, is 30. The lower bound is (Round to two decimal places as needed.) The upper bound is. (Round to two decimal places as needed.) How does increasing the sample size affect the width of the interval? The width increases The width decreases O The width does not change (c) Construct a 98% confidence interval for o2 if the sample size, n, is 20. The lower bound is . (Round to two decimal places as needed.) The upper bound is. (Round to two decimal places as needed.) Compare the results with those obtained in part (a). How does increasing the level of confidence affect the confidence interval? The width increases

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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5.STATISTICAL INFERENCE
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