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 - Mathematics and Statistics

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Sum

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 bxy and byx are negative,

r is also negative.

∴ r = – 0.5

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

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