Re: [商管] [統計]-東吳98-財務工程與精算數學-貝ꐠ…
看板Grad-ProbAsk作者alice90426 (IceSnowSmart)時間16年前 (2009/11/11 22:31)推噓2(2推 0噓 5→)留言7則, 2人參與討論串2/2 (看更多)
: 1.
: There are two types of driver. Good driver makes 75% of the population and
: in one year have zero claims with probability 0.7, one claim with probability
: 0.2, and two claims with probability 0.1. Bad drivers makes up 25% of the
: population and have zero, one, or two claims with probability 0.5, 0.3, 0.2,
: respectively. For a particular policyholder, suppose we have observed zero
: claim in year 1 and one claim in year 2.
: 1) What is the probability that the policyholder is a good driver?
Pr(所求)=0.75*0.7*0.2/[0.75*0.7*0.2+0.25*0.5*0.3]
=14/19
: 2) What is the probability that the policyholder makes no claims next year?
Pr(所求)=14/19*0.7+5/19*0.5=123/190
: 3) What is the expected number of claims next year? What is the Variance?
Pr(0 claim)=123/190
Pr(1 claim)=14/19*0.2+5/19*0.3=43/190
Pr(2 claim)=14/19*0.1+5/19*0.2=24/190=12/95
E(X)=[43/190]*1+[12/95]*2=91/190
Var(X)=123/190*[91/190]^2+43/190*[99/190]^2+12/95*[289/190]^2=0.5021
訂正了變異數 第一次算沒算到0 claim的
--
參考答案 歡迎討論
--
※ 發信站: 批踢踢實業坊(ptt.cc)
◆ From: 59.120.53.85
推
11/12 00:30, , 1F
11/12 00:30, 1F
→
11/12 00:34, , 2F
11/12 00:34, 2F
→
11/12 00:38, , 3F
11/12 00:38, 3F
推
11/12 00:42, , 4F
11/12 00:42, 4F
→
11/12 09:03, , 5F
11/12 09:03, 5F
→
11/12 09:05, , 6F
11/12 09:05, 6F
→
11/12 09:06, , 7F
11/12 09:06, 7F
※ 編輯: alice90426 來自: 140.114.32.87 (11/12 13:11)
討論串 (同標題文章)