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Question
If the two regression coefficients are 0.8 and 0.2, then the value of coefficient of correlation r will be ______.
Options
± 0.4
± 0.16
0.4
0.16
Solution
If the two regression coefficients are 0.8 and 0.2, then the value of coefficient of correlation r will be 0.4
Explanation:
Coefficient of correlation r is given by
r2 = byx . bxy
= 0.8 × 0.2
= 0.16
r = `sqrt(0.16)`
= 0.4 ...`{{:(∵ 0.8"," 0.2 > 0),(∴ r > 0):}`
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