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Question
The random variables have regression lines 3x + 2y − 26 = 0 and 6x + y − 31 = 0. Calculate co-efficient of correlations.
Solution
On finding we get,
byx = `-1/6`,
bxy = `-3/2`
∴ r2 = byx × bxy
= `-1/6 xx -3/2`
= `1/4`
∴ r = `-1/2` ...[∵ byx, bxy and r must have same sign]
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