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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 Y for X = 50.
Solution
Here, `bar x = 53, bar y = 28, "b"_"YX" = - 1.2, "b"_"XY" = - 0.3`
The regression equation of Y on X is
`("Y" - bar y) = "b"_"YX" ("X" - bar x)`
∴ (Y - 28) = (- 1.2)(X - 53)
∴ Y - 28 = - 1.2 X + 63.6
∴ Y = - 1.2 X + 63.6 + 28
∴ Y = - 1.2 X + 91.6
For X = 50
∴ Y = - 1.2(50) + 91.6 = - 60 + 91.6 = 31.6
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