Statistics for Business: Decision Making and Analysis, 3rd Edition

Think About It

1. 23. No. Square the correlation. These share ¼ of their variation.

2. 25. No. Least squares minimizes vertical deviations. If reversed, the deviations are horizontal in the plot of y on x.

3. 27. s_e = $32. If bell−shaped, then ±2 s_e holds about 95% of the residuals.

4. 29. The slope becomes steeper, producing a higher cost per mile driven. The intercept would increase as well.

5. 31. They are the same.

6. 33.

   1. Yes. The equation has a constant plus 85 times the number of shoppers.

   2. The intercept is about 0 but is likely to be a large extrapolation.

   3. The slope is about 85$/shopper.

   4. The variation may increase.

7. 35.

   1. The intercept of $47,000 is likely an extrapolation and not directly interpretable. The slope is $650 per square foot. For every one−square−foot ...