For a Poisson process with rate m per unit time, the waiting time to the first event is an exponential distribution with expected value 1/m.
For a stable population (a life table), the life expectancy is 1 over the crude death rate.
Sincerely,
David Smith
[log in to unmask]
You may leave the list at any time by sending the command
SIGNOFF allstat
to [log in to unmask], leaving the subject line blank.
|