In: Statistics and Probability
Calculate and record the regression equation. Write a paragraph discussing the slope of the regression equation and how it relates to your topic. Use the following data points.
| Height (in.) | Foot Length (in.) |
| 63 | 10 |
| 66 | 12 |
| 62.5 | 9.4 |
| 74 | 10.5 |
| 70 | 11.3 |
| 72 | 11.3 |
| 71 | 12.5 |
| 64 | 9.1 |
| 72 | 10.9 |
| 71 | 10 |
| 74 | 12.1 |
| 67 | 10 |
| 69 | 11.1 |
| 65 | 9.6 |
| 62.8 | 9 |
| 72 | 11.3 |
| 68.8 | 10.5 |
| 69 | 10 |
| 65.3 | 9 |
| 53 | 7 |
| 71 | 10.3 |
| 74 | 11.7 |
| 70 | 10 |
| 72 | 10.6 |
| 72.5 | 12.8 |
| 67 | 9.5 |
| 69 | 10.9 |
| 74 | 11.6 |
| 68 | 9 |
| 70.1 | 10.1 |
| 62 | 8 |
| 77 | 11.4 |
| 63 | 9.5 |
| 64.5 | 9.4 |
| 71 | 9.8 |
| X-Mx | Y-My | (X-Mx)^2 | (X-Mx)(Y-MY) |
| -5.471 | -0.32 | 29.937 | 1.751 |
| -2.471 | 1.68 | 6.108 | -4.152 |
| -5.971 | -0.92 | 35.658 | 5.494 |
| 5.529 | 0.18 | 30.565 | 0.995 |
| 1.529 | 0.98 | 2.337 | 1.498 |
| 3.529 | 0.98 | 12.451 | 3.458 |
| 2.529 | 2.18 | 6.394 | 5.512 |
| -4.471 | -1.22 | 19.994 | 5.455 |
| 3.529 | 0.58 | 12.451 | 2.047 |
| 2.529 | -0.32 | 6.394 | -0.809 |
| 5.529 | 1.78 | 30.565 | 9.841 |
| -1.471 | -0.32 | 2.165 | 0.471 |
| 0.529 | 0.78 | 0.279 | 0.412 |
| -3.471 | -0.72 | 12.051 | 2.499 |
| -5.671 | -1.32 | 32.165 | 7.486 |
| 3.529 | 0.98 | 12.451 | 3.458 |
| 0.329 | 0.18 | 0.108 | 0.059 |
| 0.529 | -0.32 | 0.279 | -0.169 |
| -3.171 | -1.32 | 10.058 | 4.186 |
| -15.471 | -3.32 | 239.365 | 51.365 |
| 2.529 | -0.02 | 6.394 | -0.051 |
| 5.529 | 1.38 | 30.565 | 7.629 |
| 1.529 | -0.32 | 2.337 | -0.489 |
| 3.529 | 0.28 | 12.451 | 0.988 |
| 4.029 | 2.48 | 16.229 | 9.991 |
| -1.471 | -0.82 | 2.165 | 1.207 |
| 0.529 | 0.58 | 0.279 | 0.307 |
| 5.529 | 1.28 | 30.565 | 7.077 |
| -0.471 | -1.32 | 0.222 | 0.622 |
| 1.629 | -0.22 | 2.652 | -0.358 |
| -6.471 | -2.32 | 41.879 | 15.014 |
| 8.529 | 1.08 | 72.737 | 9.211 |
| -5.471 | -0.82 | 29.937 | 4.487 |
| -3.971 | -0.92 | 15.772 | 3.654 |
| 2.529 | -0.52 | 6.394 | -1.315 |
| Mx: 68.471 | My: 10.320 | Sum: 772.351 | Sum: 158.830 |
Sum of X = 2396.5
Sum of Y = 361.2
Mean X = 68.4714
Mean Y = 10.32
Sum of squares (SSX) = 772.3514
Sum of products (SP) = 158.83
Regression Equation = ŷ = bX + a
b = SP/SSX = 158.83/772.35 =
0.2056
a = MY - bMX = 10.32 -
(0.21*68.47) = -3.7608
ŷ = 0.2056X - 3.7608
The slope of a regression line (b) represents the rate of change in y as x changes. Because y is dependent on x, the slope describes the predicted values of y given x.
For this case for every increase in x, y will increase by 0.2056