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Question
For bivariate data. `bar x = 53`, `bar y = 28`, byx = −1.2, bxy = −0.3. Find the correlation coefficient between x and y.
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Solution
Given:
`bar x = 53`,
`bar y = 28`,
byx = −1.2,
bxy = −0.3.
Correlation coefficient between x and y:
r = `+-sqrt("b"_"xy" * "b"_"yx")`
`= +- sqrt((-0.3)(-1.2))`
= `+- sqrt 0.36`
= ± 0.6 ...[∵ byx and bxy are negative]
Since byx and bxy both are negative,
r is also negative.
∴ r = −0.6
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