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Question: Using the summary statistics in Exercise 4,

Using the summary statistics in Exercise 4, and assuming that the data come from a distribution that is Normally distributed, a) Find a 95% confidence interval for the mean difference in page views from the two websites. b) Why is the confidence interval narrower than the one you found in Exercise 10? c) Is 0 within the confidence interval? d) What does it say about the null hypothesis that the mean difference is 0? Exercise 4: Not happy with the previous results, the analyst in Exercise 2 takes a much larger random sample of customers from each website and records their page views. Here are the data:
Using the summary statistics in Exercise 4, and assuming that the data come from a distribution that is Normally distributed, 
a) Find a 95% confidence interval for the mean difference in page views from the two websites. 
b) Why is the confidence interval narrower than the one you found in Exercise 10? 
c) Is 0 within the confidence interval? 
d) What does it say about the null hypothesis that the mean difference is 0?

Exercise 4:
Not happy with the previous results, the analyst in Exercise 2 takes a much larger random sample of customers from each website and records their page views. Here are the data:


a) Find the estimated mean difference in page visits between the two websites.
b) Find the standard error of the estimated mean difference.
c) Calculate the t-statistic for the observed difference in mean page visits assuming that the true mean difference is 0.

a) Find the estimated mean difference in page visits between the two websites. b) Find the standard error of the estimated mean difference. c) Calculate the t-statistic for the observed difference in mean page visits assuming that the true mean difference is 0.





Transcribed Image Text:

Website A Website B m = 80 h = 1.7 pages = 1.3 pages 51 = 4.6 pages Sz = 4.3 pages = 95


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