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Question
The equations of the two lines of regression are 2x + 3y − 6 = 0 and 5x + 7y − 12 = 0. Find the value of the correlation coefficient `("Given" sqrt(0.933) = 0.9667)`
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Solution
r = `+- sqrt("b"_(xy) * "b"_(yx))`
= `+- sqrt((-7)/5 xx (-2)/3)`
= `+- sqrt(0.933)`
= 0.9667
Since the values of bXY and bYX are negative,
r is also negative.
∴ r = – 0.9667
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