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Question
Choose the correct alternative:
|byx + bxy| ≥ ______
Options
|r|
2|r|
r
– r
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Solution
2|r|
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Mean of x = `barx = square`
Mean of y = `bary = square`
bxy = `square/square`
byx = `square/square`
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∴ Regression equation of y on x is `square`
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Mean of y = 20
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`sigma_y` = 3
r = 0.5
byx = `square`
bxy = `square`
when x = 10,
`y - square = square (10 - square)`
∴ y = `square`
bXY . bYX = ______.
