Gibbs update for dyadic variance
rs2_fc(Z, rho,offset=0,nu0=NULL,s20=NULL)
a new value of s2
n X n normal relational matrix
current value of rho
matrix of the same dimension as Z. It is assumed that Z-offset
is equal to dyadic noise, so the offset should contain any additive and
multiplicative effects (such as Xbeta(X,beta+ U%*%t(V) +
outer(a,b,"+")
)
prior degrees of freedom
prior estimate of s2
Peter Hoff