statistics
posted by Kevin .
I need to prove this
σ(hat)^2(x,y) = (1/n) Σ (Xi  X (bar) ) Yi
using
σ(hat)^2(x,y)= (1/n) Σ (Xi  X(bar)) (YiY(bar))
and
X(bar)= (1/n) Σ Xi
σ(hat)^2 (x,y) is the estimator of covariance
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