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प्रश्न
The equations of the two lines of regression are 6x + y − 31 = 0 and 3x + 2y – 26 = 0. Identify the regression lines
उत्तर
Let 3x + 2y – 26 = 0 be the regression equation of Y on X
∴ The equation becomes 2Y = −3X + 26
i.e., Y = `(-3)/2 "X" + 26/2`
Comparing it with Y = bYX X + a, we get
bYX = `(-3)/2`
Now, the other equation 6x + y − 31 = 0 is the regression equation of X on Y.
∴ The equation becomes 6X = − Y + 31
i.e., X = `(-1)/6 "Y" + 31/6`
Comparing it with X = bXY Y+ a', we get
bxy = `(-1)/6`
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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`
