Function calculates value of variational parameter using maximum likelihood.
expectedXi(theta, mu, mi, psi, Ci)
A vector of variational parameters for the current subject.
spline basis functions for the current subject.
vector of spline coefficients for the population mean.
vector of expected mean scores for the current subject.
matrix of spline coefficients for the principal component basis functions.
expected covariance matrix of scores for the current subject.