Mean or Variance equation with GARCH model

[bsinnott1]

Hi,

I was wondering if you could clear something up for me I am using a multivariate GARCH model to test the time series relationship between the variance of gold returns against its own lags and against the variance of equity and bond returns. Should the variances of these exogenous variables be entered in the variance or mean equation. Sorry if this question is a little too straight forward but I have searched my econometics text book and GARCH regression literature to decifer which equation these variables belong in and I cant seem to find the answer I am looking for. Your help with this matter would be greatly appreciated.

Kind Regards,