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 (Given0.933=0.9667) - Mathematics and Statistics

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Sum

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

Concept: Properties of Regression Coefficients
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Chapter 2.3: Linear Regression - Q.4

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