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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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Sales (₹ in lakh) (Y) | |
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| Standard Mean | 3 | 12 |
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| Mean | 85 | 90 |
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| Sales | Adv. Exp. | |
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If u = `(x - 20)/5` and v = `(y - 30)/4`, then byx = ______
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If n = 5, Σx = Σy = 20, Σx2 = Σy2 = 90 , Σxy = 76 Find Covariance (x,y)
Mean of x = 53
Mean of y = 28
Regression coefficient of y on x = – 1.2
Regression coefficient of x on y = – 0.3
a. r = `square`
b. When x = 50,
`y - square = square (50 - square)`
∴ y = `square`
c. When y = 25,
`x - square = square (25 - square)`
∴ x = `square`
The regression equation of y on x is 2x – 5y + 60 = 0
Mean of x = 18
`2 square - 5 bary + 60` = 0
∴ `bary = square`
`sigma_x : sigma_y` = 3 : 2
∴ byx = `square/square`
∴ byx = `square/square`
∴ r = `square`
