概车纶与款理统外 解n=50,m=15, s(t1s)=115+119+.+170+172+(50-15)×172 =8270, 0的最大似然估计值为 0=8270 15 =551.33(小时)解 n = 50, m = 15, s(t 1 5 ) = 115 + 119 ++ 170 + 172 + (50 −15)172 = 8270,  的最大似然估计值为 15 8270  ˆ = = 551.33 (小时)