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Question: Using the data in Exercise 1, and

Using the data in Exercise 1, and assuming that the data come from a distribution that is Normally distributed, a) Find a 95% confidence interval for the mean difference in ages of houses in the two neighborhoods. b) Is 0 within the confidence interval? c) What does it say about the null hypothesis that the mean difference is 0? Exercise 1: A developer wants to know if the houses in two different neighborhoods were built at roughly the same time. She takes a random sample of six houses from each neighborhood and finds their ages from local records. The table shows the data for each sample (in years).
Using the data in Exercise 1, and assuming that the data come from a distribution that is Normally distributed, 
a) Find a 95% confidence interval for the mean difference in ages of houses in the two neighborhoods. 
b) Is 0 within the confidence interval? 
c) What does it say about the null hypothesis that the mean difference is 0? 

Exercise 1:
A developer wants to know if the houses in two different neighborhoods were built at roughly the same time. She takes a random sample of six houses from each neighborhood and finds their ages from local records. The table shows the data for each sample (in years).


a) Find the sample means for each neighborhood.
b) Find the estimated difference of the mean ages of the two neighborhoods.
c) Find the sample variances for each neighborhood.
d) Find the sample standard deviations for each neighborhood.
e) Find the standard error of the difference of the two sample means.

a) Find the sample means for each neighborhood. b) Find the estimated difference of the mean ages of the two neighborhoods. c) Find the sample variances for each neighborhood. d) Find the sample standard deviations for each neighborhood. e) Find the standard error of the difference of the two sample means.





Transcribed Image Text:

Neighborhood 1 Neighborhood 2 57 50 60 43 46 35 62 53 67 56 55


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