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प्रश्न
Bring out the inconsistency in the following:
bYX = bXY = 1.50 and r = - 0.9
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उत्तर
Given, bYX = bXY = 1.50 and r = - 0.9
Here, the coefficient of regressions is positive and the coefficient of correlation is negative.
But, for consistent data they must have the same signs.
∴ The given data is inconsistent.
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संबंधित प्रश्न
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| Mean | 25 | 20 |
| S.D. | 4 | 3 |
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| X | Y | |
| Mean | 85 | 90 |
| S.D. | 5 | 6 |
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| Sales | Adv. Exp. | |
| Mean | 40 | 6 |
| S.D. | 10 | 1.5 |
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| X | Y | |
| Mean | 13 | 17 |
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The regression equation of y on x is 2x – 5y + 60 = 0
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∴ `bary = square`
`sigma_x : sigma_y` = 3 : 2
∴ byx = `square/square`
∴ byx = `square/square`
∴ r = `square`
| 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`
The following results were obtained from records of age (x) and systolic blood pressure (y) of a group of 10 women.
| x | y | |
| Mean | 53 | 142 |
| Variance | 130 | 165 |
`sum(x_i - barx)(y_i - bary)` = 1170
