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Question
Choose the correct alternative:
If the lines of regression of Y on X is y = `x/4` and X on Y is x = `y/9 + 1` then the value of r is
Options
`1/6`
0
`- 1/4`
`- 1/6`
Solution
`1/6`
RELATED QUESTIONS
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The regression equation of y on x is 8x – 10y + 66 = 0 ......(ii)
Solving equations (i) and (ii),
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`bary = square`
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∴ bxy = `square/square`
∴ r = `square`
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Solution:
Given:`n=8,sum(x_i-barx)=36,sum(y_i-bary)^2=40,sum(x_i-barx)(y_i-bary)=24`
∴ `b_(yx)=(sum(x_i-barx)(y_i-bary))/(sum(x_i-barx)^2)=square`
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For a bivariate data `barx = 10`, `bary = 12`, V(X) = 9, σy = 4 and r = 0.6
Estimate y when x = 5
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∴ Y − 12 = `r.(σ_y)/(σ_x)("X" - 10)`
∴ Y − 12 = `0.6 xx 4/square ("X" - 10)`
∴ When x = 5
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∴ Y − 12 = −4
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Following is the data that the Manager refers to:
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- If a person with 13 years of experience applies for a job in this company, what monthly salary will be suggested by the Manager?
