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For a bivariate data x¯=10, y¯=12, V(X) = 9, σy = 4 and r = 0.6Estimate y when x = 5 Solution: Line of regression of Y on X is Y-y¯=□(X-x¯) ∴ Y - 12 = σσr.σyσx(X-10) ∴ Y - 12 = 0.6×4□(X-10) - Mathematics and Statistics

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Question

For a bivariate data `barx = 10`, `bary = 12`, V(X) = 9, σy = 4 and r = 0.6
Estimate y when x = 5

Solution: Line of regression of Y on X is

`"Y" - bary = square ("X" - barx)`

∴ Y − 12 = `r.(σ_y)/(σ_x)("X" - 10)`

∴ Y − 12 = `0.6 xx 4/square ("X" - 10)`

∴ When x = 5

Y − 12 = `square(5 - 10)`

∴ Y − 12 = −4

∴ Y = `square`

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Solution

Solution: Line of regression of Y on X is

`"Y" - bary = bb(b_(yx)) ("X" - barx)`

∴ Y − 12 = `r.(σy)/(σx)("X" - 10)`

∴ Y − 12 = `0.6 xx (4/bb3) ("X" - 10)`

∴ When x = 5

Y − 12 = 0.8 (5 − 10)

∴ Y − 12 = −4

∴ Y = 8

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