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Question
If bYX = − 0.6 and bXY = − 0.216, then find correlation coefficient between X and Y. Comment on it.
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Solution
Given, bYX = − 0.6, bXY = − 0.216
∴ r = `+-sqrt("b"_"XY" * "b"_"YX")`
`= +- sqrt(- 0.216 * (- 0.6)) = +- sqrt(0.1296)`
∴ r = ± 0.36
Since bXY and bYX are negative,
r is also negative.
∴ r = - 0.36
∴ X and Y negatively correlated.
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