theta
Matrix of the MSAR coeffients with $h$ rows and
$m x p + 2$ columns. The first column
is the constants, the next $m x p + 1$ columns
are the autoregressive coefficients (by lag -- so the first $m x 1$ are the AR(1) coefficients, etc.) and the last
$ m x 1$ elements are the error variances (remember,
this is univariate!)