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Question
For bivariate data. `bar x = 53, bar y = 28, "b"_"YX" = - 1.2, "b"_"XY" = - 0.3` Find estimate of X for Y = 25.
Solution
Here, `bar x = 53, bar y = 28, "b"_"YX" = - 1.2, "b"_"XY" = - 0.3`
The regression equation of X on Y is
`("X" - bar x) = "b"_"XY" ("Y" - bar y)`
∴ (X - 53) = (- 0.3)(Y - 28)
∴ X - 53 = - 0.3 Y + 8.4
∴ X = - 0.3 Y + 8.4 + 53
∴ X = - 0.3 Y + 61.4
For Y = 25
∴ X = - 0.3(25) + 61.4 = - 7.5 + 61.4 = 53.9
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