The file P10_10.xlsx contains data on 150 homes that were sold recently in a particular community.
a. Find a table of correlations between all of the variables. Do the correlations between Price and each of the other variables have the sign (positive or negative) you would expect? Explain briefly.
b. Run a regression of Price versus Rooms. What does the 95% confidence interval for the coefficient of Rooms tell you about the effect of Rooms on Price for the entire population of such homes?
c. Run a multiple regression of Price versus Home Size, Lot Size, Rooms, and Bathrooms. What is the 95% confidence interval for the coefficient of Rooms now? Why do you think it can be so different from the one in part b? Based on this regression, can you reject the null hypothesis that the population regression coefficient of Rooms is zero versus a two-tailed alternative? What does this mean?