ronja

Originally posted by stupid X at 2007-3-14 10:55:
"the curious incident of the dog in the night time "書中有proof, 換ge機會大d
用conditional probability prove又得
用flow chart 都得
天才真係天才

玩遊戲角度睇practically)
根本無論之前有幾多度門,player最終只係從兩度門中選其一,機會係二分之一....換唔換,睇心水....冇話一定要換...因為點換個機會都只係二分一
而之前嘅第三度(or第4,5..........100000000度)門,只係用嚟令你覺得自己冇咁好運,第一次就揀中,而遊戲主持人及觀眾亦會多咗話題,節目收視上升......etc




數學角度睇theoratically)
那個什麼天才的數學理論也不是錯的,數係咁計,有好多proof可以做去証明換係可以提升中獎機會率(但不高於二分之一),但要記住,機會率高不等於一定中



但當兩樣加埋時,就等於擲毫一樣,雖然擲公和字的機會率都是二分之一,但是否等於今次擲中字下次一定是擲公呢?連續擲六次公沒有機會發生嗎?不,只不過機會率是六十四分之一吧!


所以玩遊戲中獎是要有運氣的

ronja

我認為總之去到最尾,中唔中都只係1/2機會

所謂D1/3,2/3嘅機會率,只係响個主持開嗰度沒有車嘅門之前出現,once佢開咗度無車嘅房門,由於個condition唔同咗,所以要計個參賽者贏架車嘅機會率又唔同咗嘞!
响計probability入便,condition好緊要,要define 得清楚,condition 轉咗的話,(in this case:開咗一間冇車的房門),又要「重新」因應新condition計過個機會率嘞!
(其實仲有condition on condition 嘅case,要計埋set同subset嘅嘢,但唔想太煩)


其實我估個女天才所引用嘅道理係:

我開頭揀咗一度門,而架車响度門後面嘅機會係三分之一,架車响另外兩度門後面嘅機會「加埋」係三分之二(1/3+1/3),而當主持開咗一度冇車嘅門之後,由於嗰度門有車嘅機會率而家發現係零,所以响原本嗰兩度門後面有車而架車而家响淨低另一度門後面嘅機會率就係:

2/3 -- 0 = 2/3

that's why she insist to change her choice to the other door cos 2/3 is greater than 1/3.

ronja

Originally posted by playbr2 at 2007-3-15 00:52:
先引文一篇.... 摘自某網友

=====...

‧


根據佢講嘅condition,在打開一度空門之後,是不可能有對換對或錯換錯的情況出現的

而在打開一度空門之後(注意condition已轉了),由於當時只得換或不換,而換的話亦只得一個選擇(並不是一開始有三個選擇),所以機會率是二分之一

ronja

Originally posted by playbr2 at 2007-3-15 01:33:


那說白一点.............二分之一 是''結果的出現'',不具有好壞之分...........但e加主題係要win , 所以換或不換門 , 門同門既機率就有分別

.我....唔係好明你講乜????

而在打開一度空門之後(注意condition已轉了),由於當時只得換或不換,而換的話亦只得一個選擇(並不是一開始有三個選擇),所以機會率是二分之一

但我所講這個情況,論據是與結果冇關

[ Last edited by ronja on 2007-3-15 at 02:04 AM ]

ronja

Originally posted by hold_find at 2007-3-15 02:20:

我明白佢講乜la
佢意思係"如...

i understand what you are saying.......
can finish the dis,cussions...

[ Last edited by ronja on 2007-3-15 at 02:41 AM ]

ronja

一見當初原以為已解決之問題,又有這麼多意見....


其實一早巳提出嘅一個重點就係 define the condition 嘅問題,但大家响討論時不斷將兩個不同情况下觀衆中獎之機會率混為一談.

我諗要問清楚條問題先:

1.玩呢個遊戲嘅觀眾中獎嘅機會率係幾多?
2.玩呢個遊戲嘅觀眾响主持人開咗一度空門(一定是空啦!!)之後轉呔而中獎嘅機會率又係幾多?


如果咁問法, 我答案係:
1.二分之一
2.三分之二

大家又有咩意見呢?

Please clearly 'define your condition' b4 you comment on it.

ronja

Originally posted by kaichun88 at 2007-3-16 15:59:

一係1/3(不換),一係2/3(換)

除非...

我根據而家大家討論個問題而去設計兩個問題出嚟,你叫番我去-----'read the question'b4 you comment on it.......你都幾攪笑

i asked the 2 questions and you should be the one to 'read the questions' and answer the 2 questions!
If you say that the first question is nonsense then you are telling me that you did not even know the reason why i asked the first question, or maybe you did not even know the answer of the very simple first question!!
If one can READ the 2 questions AND THINK carefully then one will know the reason for me to post the first question is to distinguish the different conditions.You can give answers to my questions if you can but I don't think you can say any of the questions is nonsense,unless you cannot answer them

You can of course give me different answers to the questions but with your explanation please.

ronja

Originally posted by kaichun88 at 2007-3-16 22:29:

我認為#116的post完全可以解決你的...

thanks for telling me that you do not understand the first question

but please don't make the 1st question become the 2nd question,that's the reason why i ask the 1st question!

ronja

Originally posted by kaichun88 at 2007-3-17 15:32:

Would you please telling me what ...

Can't you read???

but please don't make the 1st question become the 2nd question,that's the reason why i ask the 1st question!

and i only said you do not understand the 1st question,i didn't say you misunderstand the 1st question!!if you cannot express properly in english,as you had already using the same sentence structure as mine for more than once to express your view,you can switch to chinese,i can read chinese as well.but next time,do not ask a question that i had already answered!

ronja

Originally posted by kaichun88 at 2007-3-17 18:48:

You haven't answered any question...

try to read #55
it's in chinese