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.*

Tue Jun 6 00:15:46 DF 1995