我怎么觉得从理论上讲预期寿命和平均死亡年龄就是一回事

我怎么觉得从理论上讲预期寿命和平均死亡年龄就是一回事

所有跟贴·加跟贴·新语丝读书论坛

送交者: HunHunSheng 于 2008-06-26, 22:58:21:

平均死亡年龄=sum of all age(i)/N
=Sum N(i)Age(i)/N

Let N(i)/N be the probability of dying at age i, then
you draw the conclusion

You can define 100 diffeent averages and give them 100 different names - 008 (41 bytes) 2008-06-27, 10:19:17 (238910)
预期寿命(i)=Sum(N(j)*j)/Sum(N(j)), j>=i. N(j)是在年龄j死亡总数. - whiteshark (85 bytes) 2008-06-27, 07:55:17 (238901)
Sorry. But N(i)/N is NOT the probability of dying at age i of a newborn. (无内容) - wasguru (0 bytes) 2008-06-27, 02:09:59 (238883)