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If bYX = − 0.6 and bXY = − 0.216, then find correlation coefficient between X and Y. Comment on it.

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प्रश्न

If bYX = − 0.6 and bXY = − 0.216, then find correlation coefficient between X and Y. Comment on it.

योग
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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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Properties of Regression Coefficients
  क्या इस प्रश्न या उत्तर में कोई त्रुटि है?
अध्याय 3: Linear Regression - Miscellaneous Exercise 3 [पृष्ठ ५४]

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बालभारती Mathematics and Statistics 2 (Commerce) [English] Standard 12 Maharashtra State Board
अध्याय 3 Linear Regression
Miscellaneous Exercise 3 | Q 4.12 | पृष्ठ ५४

संबंधित प्रश्न

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If the two regression lines for a bivariate data are 2x = y + 15 (x on y) and 4y = 3x + 25 (y on x), find

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bxy and byx are ______


Choose the correct alternative:

Both the regression coefficients cannot exceed 1


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If bxy < 0 and byx < 0 then ‘r’ is > 0


State whether the following statement is True or False: 

If u = x – a and v = y – b then bxy = buv 


State whether the following statement is True or False:

Cov(x, x) = Variance of x


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(₹ in lakhs)
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(₹ in lakhs)
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Mean of y = 28

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Regression coefficient of x on y = – 0.3

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∴ x = `square`


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6 9 54 36 81
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byx = `square/square`

∴ Regression equation of x on y is `square`

∴ Regression equation of y on x is `square`


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