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प्रश्न
If bYX = − 0.6 and bXY = − 0.216, then find correlation coefficient between X and Y. Comment on it.
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उत्तर
Given, bYX = − 0.6, bXY = − 0.216
∴ r = `+-sqrt("b"_"XY" * "b"_"YX")`
`= +- sqrt(- 0.216 * (- 0.6)) = +- sqrt(0.1296)`
∴ r = ± 0.36
Since bXY and bYX are negative,
r is also negative.
∴ r = - 0.36
∴ X and Y negatively correlated.
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संबंधित प्रश्न
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bxy = `square`
when x = 10,
`y - square = square (10 - square)`
∴ y = `square`
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| 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`
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∴ Regression equation of x on y is `square`
∴ Regression equation of y on x is `square`
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