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Question
Choose the correct alternative:
bxy and byx are ______
Options
Independent of change of origin and scale
Independent of change of origin but not of scale
Independent of change of scale but not of origin
Affected by change of origin and scale
Solution
Independent of change of origin but not of scale
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| x | y | xy | x2 | y2 |
| 6 | 9 | 54 | 36 | 81 |
| 2 | 11 | 22 | 4 | 121 |
| 10 | 5 | 50 | 100 | 25 |
| 4 | 8 | 32 | 16 | 64 |
| 8 | 7 | `square` | 64 | 49 |
| Total = 30 | Total = 40 | Total = `square` | Total = 220 | Total = `square` |
bxy = `square/square`
byx = `square/square`
∴ Regression equation of x on y is `square`
∴ Regression equation of y on x is `square`
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| x | y | |
| Mean | 53 | 142 |
| Variance | 130 | 165 |
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