A real estate agent developed a model to relate a house's selling price (Y) to the area of floor space (X) and the area of floor space squared (X2). The multiple regression equation for this model is: Y = 125 - 3X + X2 where: Y = selling price (times $1,000) X = square feet of floor space (times 100) What is the y- intercept (a)?

A) $125 000 B) $125 C) $3000 D) $-3000 A) $125 000 B) $125 C) $3000 D) $-3000

The following summary is from home heating costs, using mean outside temperature as X1 the number of centimeters of insulation as X2, and the presence of a garage as X3. Is the presence of the independent variable garage significant in predicting heating costs, when tested at the 0.05 level of significance?

A) Since the p-value is less than the level of significance, the null hypothesis is rejected, and so the garage should be included in the analysis. B) Since the p-value is less than the level of significance, the null hypothesis is accepted, and so the garage should not be included in the analysis. C) Since the p-value is more than the level of significance, the null hypothesis is accepted, and so the garage should not be included in the analysis. D) Since the p-value is more than the level of significance, the null hypothesis is rejected, and so the garage should be included in the analysis. A) Since the p-value is less than the level of significance, the null hypothesis is rejected, and so the garage should be included in the analysis. B) Since the p-value is less than the level of significance, the null hypothesis is accepted, and so the garage should not be included in the analysis. C) Since the p-value is more than the level of significance, the null hypothesis is accepted, and so the garage should not be included in the analysis. D) Since the p-value is more than the level of significance, the null hypothesis is rejected, and so the garage should be included in the analysis.

A sample of General Mills employees was studied to determine their degree of satisfaction with their present life. A special index, called the index of satisfaction, was used to measure satisfaction. Six factors were studied: age at the time of first marriage (X1), annual income (X2), number of children living (X3), value of all assets (X4), status of health in the form of an index (X5), and the average number of social activities per week (X6). Suppose the multiple regression equation is: Y' = 16.24 + 0.017X1 + 0.00028X2 +42X3 + 0.0012X4 + 0.09X5 + 26.8X6. Explain the meaning of b3.

A) For each additional living child, their satisfaction index is expected to increase by 4.2 points. B) For each additional living child, their satisfaction index is expected to increase by 42 points. C) For each additional living child, their satisfaction index is expected to increase by 0.42 points. D) For each additional$1,000 of annual income, their satisfaction index is expected to increase by 0.028 points. E) For each additional$1,000 of annual income, their satisfaction index is expected to increase by 2.8 points. A) For each additional living child, their satisfaction index is expected to increase by 4.2 points. B) For each additional living child, their satisfaction index is expected to increase by 42 points. C) For each additional living child, their satisfaction index is expected to increase by 0.42 points. D) For each additional$1,000 of annual income, their satisfaction index is expected to increase by 0.028 points. E) For each additional$1,000 of annual income, their satisfaction index is expected to increase by 2.8 points.