=4-16 Steve Caples, a real estate appraiser in Lake Charles, Louisiana, has developed a regression model to help appraise residential housing in the Lake Charles area. The model was developed using recently sold homes in a particular neighborhood. The price (Y) of the house is based on the square footage (X) of the house. The model is

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Y X = + 33, . 478 62 4 The coefficient of correlation for the model is 0.63.

(a) Use the model to predict the selling price of a house that is 1,860 square feet.

(b) A house with 1,860 square feet recently sold for $165,000. Explain why this is not what the model predicted.

(c) If you were going to use multiple regression to develop an appraisal model, what other quantitative variables might be included in the model?

(d) What is the coefficient of determination for this model?