2. Enterprise Industries produces Fresh, a brand of liquid laundry detergent. In order to study the relationship between price and demand for Fresh, the company has gathered data concerning demand for Fresh over the last 30 weeks. For each week, y is the demand for Fresh (in hundreds of thousands of bottles) during that week, x, is the price of Fresh during that week (in dollars), x, is the average industry price of similar detergents offered by competitors (in dollars), and xz is the expenditure on advertising by Enterprise Industries. The estimation of a multiple linear model by OLS produces the following table: Regression Statistics Multiple R R Square Adjusted R Square Standard Error Observations 0.9453 0.8936 0.8813 0.2347 30 F 72.797 Significance F 8.883E-13 ANOVA Regression Residual Total df 3 26 29 SS MS 12.0268 4.0089 1.4318 0.0551 13.4586 Standard Error t Stat 2.4450 3.1039 0.6379 -3.6958 0.2954 5.4585 0.1259 3.9814 Coefficients 7.5891 -2.3577 1.6122 0.5012 Intercept Price (X1) IndPrice (X2) AdvExp (x3) P-value 0.0046 0.0010 0.0000 0.0005 Upper 95% 12.6149 -10464 22190 0.7599 Lower 95% 25633 -3.6690 1.0051 0.2424 a. What are the least square estimates of bo, by, by, and by? b. Interpret the values of bo, by, b2, and bz. c. Can you reject the null hypothesis that the effects of all three independent variables on demand are equal to zero?
2. You would like to check if the average wage of Danish men and women is the same. In order to do that, you obtain a sample of 100 men and 50 women from Denmark. Explain how you would conduct this test under the following assumption: a. The two populations have the same variance b. The two populations different variances