The covariance, denoted cov, is computed from:
cov = 1/(n-1) * [E](X - X(bar))(Y - Y(bar))
a. cov / s(subx)
b. cov / (s(subx) * s(suby))
c. cov / s(subx)^2
d. cov / s(suby)^2
e. (s(suby) / s(subx)) * cov
Answer: b. cov / (s(subx) * s(suby))
cov = 1/(n-1) * [E](X - X(bar))(Y - Y(bar))
What is the formula for the correlation coefficient in terms of the cov?
a. cov / s(subx)
b. cov / (s(subx) * s(suby))
c. cov / s(subx)^2
d. cov / s(suby)^2
e. (s(suby) / s(subx)) * cov
Answer: b. cov / (s(subx) * s(suby))
Learn More :
Correlation and Regression Analysis
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