Multiple choice questions based on multiple regression.
1. A regression model between sales (Y in $1,000), unit price (X1 in dollars) and television advertisement (X2 in dollars) resulted in the following function: = 7 - 3X1 + 5X2. For this model SSR = 3500, SSE = 1500, and the sample size is 18. The coefficient of the unit price indicates that if the unit price is
1. increased by $1 (holding advertising constant), sales are expected to increase by $3
2. decreased by $1 (holding advertising constant), sales are expected to decrease by $3
3. increased by $1 (holding advertising constant), sales are expected to increase by $4,000
4. increased by $1 (holding advertising constant), sales are expected to decrease by $3,000
2. In a regression model involving 30 observations, the following estimated regression equation was obtained: Y = 17 + 4X1 - 3X2 + 8X3 + 8X4. For this model SSR = 700 and SSE = 100. The coefficient of determination for the above model is approximately
1. -0.875
2. 0.875
3. 0.125
4. 0.144