To study the water PH level, two independent lakes were selected for sampling. In a durationof one year, 12 samples (one in each month) are selected from each lake. water samples aretaken from two different lakes. The PH mean and standard deviation of lake 1 sample werefound to be 6.5 and 0.2, while the PH mean and standard deviation of lake 2 sample were foundto be 7.2 and 0.1.(a) Find a 90% confidence interval for Hi – H2 (i.e., the difference between the population meansfor the two lakes) assuming that the populations are approximately normally distributed with equalvariances.(b) You decide to decrease the above significance level from 0.1 to 0.01. Everything else is keptsimilar to above. Explain how your calculated confidence interval will change, and why? (i.e., willit become wider or narrower). (No need to calculate the new confidence interval)

To study the water PH level, two independent lakes were selected for sampling. In a duration of one year, 12 samples (one in each month) are selected from each lake. water samples are taken from two different lakes. The PH mean and standard deviation of lake 1 sample were found to be 6.5 and 0.2, while the PH mean and standard deviation of lake 2 sample were found to be 7.2 and 0.1. (a) Find a 90% confidence interval for 41 - Hz (i.e., the difference between the population means for the two lakes) assuming that the populations are approximately normally distributed with equal variances. (b) You decide to decrease the above significance level from 0.1 to 0.01. Everything else is kept similar to above. Explain how your calculated confidence interval will change, and why? (i.e., will it become wider or narrower). (No need to calculate the new confidence interval)

To study the water PH level, two independent lakes were selected for sampling. In a duration of one year, 12 samples (one in each month) are selected from each lake. water samples are taken from two different lakes. The PH mean and standard deviation of lake 1 sample were found to be 6.5 and 0.2, while the PH mean and standard deviation of lake 2 sample were found to be 7.2 and 0.1. (a) Find a 90% confidence interval for 41 - Hz (i.e., the difference between the population means for the two lakes) assuming that the populations are approximately normally distributed with equal variances. (b) You decide to decrease the above significance level from 0.1 to 0.01. Everything else is kept similar to above. Explain how your calculated confidence interval will change, and why? (i.e., will it become wider or narrower). (No need to calculate the new confidence interval)

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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