作者oceanboy0605 ()
看板Statistics
標題[問題]統計三個問題
時間Fri Jan 4 22:01:15 2008
以下我有統計三題我各位幫忙，除了有過程之外，
最好需要有詳細解說我會比較容易瞭解～謝謝
1.求算二項分配的眾數
2.If 5% of the tires purchased by a cab company last less than 6 months
and if 20 tires are purchased, calculate the probability that at most
2 of the tires will expire in six months using.
If the mean length of life a tire 2 years. Use the exponential distribution
to calculate the probability that the life of a tire will be less than
6 months?
3.Suppose the lifelime of an electronic tube has an exponential distribution
with a mean time of 1/λ hours. Find the expected lifelime of a tube,given
that the tube has lasted at least T hours.
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1F：推 ashugh:第2題第一部分就是binomial,第二部分跟第三題用exponential 01/04 22:05
2F：→ ashugh:distribution去算就ok了啊! 01/04 22:06
3F：→ ashugh:至於第一題直覺是F(x)=0.5 01/04 22:08
4F：推 ashugh:感覺有說跟沒說一樣XD! 2.1 P(X<=2) X~bi(n=20,p=0.95) 01/04 22:11
5F：→ ashugh:2.2 P(Y<0.5) Y~exp(2) Q3 E(Y given Y>T) Y~exp(1/λ) 01/04 22:14
6F：推 lbbear:f(a)>f(a+1) & f(a)>f(a-1) 滿足的都是眾數 01/05 20:32