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प्रश्न
Values of two regression coefficients between the variables X and Y are `b_"yx" = - 0.4` and `b_"xy"` = - 2.025 respectively. Obtain the value of correlation coefficient.
उत्तर
Correlation coefficient is
`r = ±sqrt(b_"yx".b_"xy")`
`r = ±sqrt(-2.025 xx - 0.4)`
`r = ±sqrt(0.81)`
⇒ r = -0.9 (∵ `b_"yx" and b_"xy"` are negative)
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