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For a Bivariate Data, ¯ X = 53 , ¯ Y = 28 , B Xy = − 0.2 , B Yx = − 1.5 Find Estimate of Y , When X = 50. - Mathematics and Statistics

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प्रश्न

For a bivariate data, 

`bar x = 53 , bar y = 28 , "b"_"xy" = - 0.2` , `"b"_"yx" = -1.5` Find 

 Estimate of Y , When X = 50. 

योग

उत्तर

Equation of regression of y on x is 

`"Y" - bar y = "b"_"yx"  ("X" - bar x)`

Y - 28 = - 1.5 (X - 53)

Y = - 1.5 X + 79.5 + 28

when X = 50 ,

Y = - 1.5 (50) + 107.5

Y = - 75 + 107.5

Y = 32.5

∴ Estimate of Y when X = 50 is 32.5

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Regression Coefficient of X on Y and Y on X
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2015-2016 (July)

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