0 
3 
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to the tail of the recurrence tine distribution,i.e. to p . 
More directly, the vector of steady state probabilities 
can be derived from the following two conditions; 
U K = ? U K_1 
U Q = + qu 1 + qu 2 + ... jsf 
\ 
■The first condition ensures the invariance of the steady 
state; the seco.nd ensures that entries to and emits fron 
the income population balance. 
It follows that 
= P* u 0 / 
u Q =1 - p p < 1 
The result.is, of course, identical with the distribution 
of the spent waiting time,derived above. 
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