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

... Estimated MPG
2	38.2 − 4.23 × 2 = 29.74	0.39 + 1.12 × 2 = 2.63	100/2.63 ≈ 38.0
3	38.2 − 4.23 × 3 = 25.51	0.39 + 1.12 × 3 = 3.75	100/3.75 ≈ 26.7
4	38.2 − 4.23 × 4 = 21.28	0.39 + 1.12 × 4 = 4.87	100/4.87 ≈ 20.5
5	38.2 − 4.23 × 5 = 17.05	0.39 + 1.12 × 5 = 5.99	100/5.99 ≈ 16.7
6	38.2 − 4.23 × 6 = 12.82	0.39 + 1.12 × 6 = 7.11	100/7.11 ≈ 14.1

The scatterplot in Figure 20.9 shows the linear fit of MPG on weight (orange) together with the curve produced by the reciprocal equation (green).

Figure 20.9 Comparing predictions from two models.

The curve produced by transforming MPG using the reciprocal captures the bend that we saw in the ...