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The equations of the two lines of regression are 6x + y − 31 = 0 and 3x + 2y – 26 = 0. Find the value of the correlation coefficient
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Solution
r = `+- sqrt("b"_(xy) * "b"_(yx))`
= `+- sqrt((-1)/6 xx (-3)/2)`
= `+- 1/2`
= `+- 0.5`
Since the values of b_{xy} and b_{yx} are negative,
r is also negative.
∴ r = – 0.5
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