Record ages at“exit”,we can know the age distribution Persons per year How many persons each ages in the 20 million who leaves this year age For a steady system,it has been proved that it is the distribution we want to know. This is an approbatory result.Today's life probability for us comes from there
16 Record ages at “exit”, we can know the age distribution For a steady system, it has been proved that it is the distribution we want to know. This is an approbatory result. Today’s life probability for us comes from there. How many persons each ages in the 20 million who leaves this year age Persons per year
Next step P电T6Pr新 /20 million age 17
17 age Persons per year /20 million Next step Persons per year
persons persons year 20million Fraction 20million year year Faditmeear1 Discontinuity E function age 18
18 age Fraction year-1 t E(t) time-1 Discontinuity E function year Fraction year 20million persons 20million year persons = =
Continuum E function(停留时间分布密度函数) E(time-1 1=E t 19
19 t E(t) time-1 t E(t) time-1 1 E(t)dt 0 = Continuum E function （停留时间分布密度函数）
E(t time 1 t F()=E(t Ffunction(停留时间分布函数) 20
20 F(t) E(t) t t d 0 = F function (停留时间分布函数） t t E(t) time-1 t E(t) time-1