Before revision:  Firstly, we provide directly computable closed form expressions for quantities appearing in the EM algorithm  . Previously, these quantities had to be estimated numerically and considerable computational speedups have been gained.
After revision:  Firstly, we provide directly computable closed form expressions for quantities appearing in the EM algorithm and associated information matrix, allowing to easily approximate confidence intervals . Previously, these quantities had to be estimated numerically and considerable computational speedups have been gained.