# how to calculate avarage variance and avarage covariance

I would like to figure out how to calculate av.variance and av.cov.

I know how to calculate portfolio variance( for large portfolio),

var(p)=1/n avarage variance+(1-1/n)avarage covariance,


If we have a pair of correlation of five asset and standard deviation of each five asset, how are we going to calculate avarage covariance and avarage variance so that we can put the data in above formula?

It confuse me because some questions avarage covariance and avarage variance are given.

thanks,i got you

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$w$ is a vector of portfolio weights.
Portfolio variance $Var(r_p)$ is:
$$Var(r_p) = w^T V w$$ where $V$ is your asset variance-covariance matrix.
Let me know if this helps: in theory $w = 1/n$ where $n$ is the number of assets should lead to some sort of "average" covariance even if I think "averages" do not really apply to this context.