Apply four portmanteau test statistics to check the validity of a fitted multivariate volatility model
MCHdiag(at, Sigma.t, m = 10)
A T-by-k matrix of residuals for a k-dimensional asset return series
The fitted volatility matrices. The dimension is T-by-k^2 matrix
The number of lags used in the tests. Default is 10.
Four test statistics and their p-values
The four test statistics are given in Tsay (2014, Chapter 7)
Tsay (2014, Chapter 7). Multivariate Time Series Analysis with R and Financial Applications. John Wiley. Hoboken, NJ.