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State whether the following statement is True or False: If bxy < 0 and byx < 0 then ‘r’ is > 0 - Mathematics and Statistics

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Question

State whether the following statement is True or False: 

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

Options

  • True

  • False

MCQ
True or False
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Solution

False

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Properties of Regression Coefficients
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Chapter 2.3: Linear Regression - Q.2

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Mean of x = 25

Mean of y = 20

`sigma_x` = 4

`sigma_y` = 3

r = 0.5

byx = `square`

bxy = `square`

when x = 10,

`y - square = square (10 - square)`

∴ y = `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`


|bxy + byz| ≥ ______.


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