Since the process is markovian, one can write:
This leads to:
involving elementary stochastic matrices
which can be directly deduced from observed data. The LSOA survey uses basic matrices instead of , therefore each matrix can be directly computed by simple products of matrix.
Most important outputs concern life expectancies which are expressed in as integer on time of a function giving the status at time t. But this function is known for each two year period, so life expectancies can be computed directly from the data without having to estimate forces.