請問這題
There are k+1 coins in a box.
The ith coin will,when flipped,turn up head withprobability i/k
,i=0,1,...,k . A coin is randomly slected from the box and is then
repeatedly filpped.
If the first n flips all results in heads, what is the conditional
probability that the (n+1)st flip will do likewise?
答案寫
P((n+1)st head | n次head)
1 1 2 k-1 k k+1
=--(--+--+.....+---+--)=----
k k k k k 2k
^^
可是不懂第一項 1/k怎麼來的@@
請問誰會呢?
--
※ 發信站: 批踢踢實業坊(ptt.cc)
◆ From: 118.167.232.78
※ 編輯: msu 來自: 118.167.232.78 (08/05 21:54)