12.19 Inventas Design, an architecture company in Norway, wants to predict the number of worker-hours necessary to finish the design of a new building in Oslo.

Relevant explanatory variables were thought to be the number of floors in the building, the weight of materials, and the number of parts it had in common with other structures built by the company. A sample of 15 of the company’s buildings was taken, and the following model was estimated:

y = b0 + b1x1 + b2x2 + b3x3 + e where y = design effort, in millions of worker-hours x1 = number of floors in the building x2 = the weight of materials, in tons x3 = percentage of parts in common with other buildings The total sum of squares and regression sum of squares were found to be as follows:

SST = 3.991 and SSR = 3.474

a. Compute and interpret the coefficient of determination.

b. Compute the error sum of squares.

c. Compute the adjusted coefficient of determination.

d. Compute and interpret the coefficient of multiple correlation.