Portfolio Active Risk

The expected portfolio active raeturn is the weighted of managers’ active returns. For portfolio active risk, must we always assume the correlation between the managers’ active returns are zero?

I would thnk so, unless given corrleation data. I doubt we will have to calculate that though.

I second that. Till now all the problems I have come across on this topic assume zero correlation for managers’ active returns.

Thanks to both. Hopefully past trend continues and no surprises this round.