Two Plus Two Older Archives  

Go Back   Two Plus Two Older Archives > General Gambling > Probability

Reply
 
Thread Tools Display Modes
  #1  
Old 12-19-2005, 10:42 PM
Guest
 
Posts: n/a
Default my math must be flawed, cuz this doesnt sound right

The chances someone gets dealt aces preflop at a 10 player table (only one person gets them):
2*10=20-->number of cards dealt out preflop
52-20=32-->number of cards not dealt
C(32,2)=561-->total number of 2 card hands that weren't dealt
[C(10,1)*C(4,2)*C(28,0)]/561=0.10695
0.10695*100=10.695% one person gets dealt aces preflop at a 10 handed table.
Now this seems too high; what did I do wrong?
Reply With Quote
  #2  
Old 12-19-2005, 10:48 PM
MagicFlea MagicFlea is offline
Senior Member
 
Join Date: Mar 2005
Posts: 106
Default Re: my math must be flawed, cuz this doesnt sound right

it should be 10 * C(4,2) / c(52,2) = minus a miniscule factor accounting for multiple rockets... 4.5 %
Reply With Quote
  #3  
Old 12-19-2005, 11:04 PM
Guest
 
Posts: n/a
Default Re: my math must be flawed, cuz this doesnt sound right

yeah i jsut figured it out to be the same thing, idiot me didnt know what iw as doing for a second. thanks though.
Reply With Quote
  #4  
Old 12-19-2005, 11:06 PM
KenProspero KenProspero is offline
Senior Member
 
Join Date: Jul 2004
Posts: 123
Default Re: my math must be flawed, cuz this doesnt sound right

Or you can just say 10/221 which gets you 4.5 % also and is close enough for gummint work.
Reply With Quote
  #5  
Old 12-20-2005, 12:19 PM
LetYouDown LetYouDown is offline
Senior Member
 
Join Date: Mar 2005
Location: Sharing a smoke w/negativity
Posts: 524
Default Re: my math must be flawed, cuz this doesnt sound right

If my A.M. inclusion/exclusion principle is correct, to meet your condition that only one person has A-A:

C(10,1) * C(4,2)/C(52,2) - C(10,2) * C(4,4)/C(52,4) = 4.5083% as opposed to 4.5249%
Reply With Quote
  #6  
Old 12-20-2005, 01:47 PM
Guest
 
Posts: n/a
Default Re: my math must be flawed, cuz this doesnt sound right

Can you explain why it would be 4.5083% opposed to 4.5249%

There are 1326 possible hand combinations with AA making up 6 of them.

6/1326 = .0045249 * ten seats = 4.5249%
Reply With Quote
  #7  
Old 12-20-2005, 02:18 PM
LetYouDown LetYouDown is offline
Senior Member
 
Join Date: Mar 2005
Location: Sharing a smoke w/negativity
Posts: 524
Default Re: my math must be flawed, cuz this doesnt sound right

Because of the "(only one person gets them)" clause. If more than one person gets them, it's counted twice.
Reply With Quote
  #8  
Old 12-20-2005, 02:53 PM
binions binions is offline
Junior Member
 
Join Date: Jan 2004
Posts: 4
Default Re: my math must be flawed, cuz this doesnt sound right

[ QUOTE ]
Or you can just say 10/221 which gets you 4.5 % also and is close enough for gummint work.

[/ QUOTE ]

I have always seen it come up trying to figure possibility of AA being out 10 handed when you have KK.

Similar roughhand calc 9*6/1225 = 4.4% ~22:1 against
Reply With Quote
  #9  
Old 12-20-2005, 04:01 PM
Guest
 
Posts: n/a
Default Re: my math must be flawed, cuz this doesnt sound right

So you are saying that with all the different permutations of the 1326 hands dealt to 10 people, whenever AA comes up twice within the 10 hands you count it TWICE towards the % of AA coming up?

That does not make mathematical sense. Once the condition (AA) is met you do not look for more satisfied conditions within the range (that set of 10 hands). You are inflating the results.
Reply With Quote
  #10  
Old 12-20-2005, 04:27 PM
LetYouDown LetYouDown is offline
Senior Member
 
Join Date: Mar 2005
Location: Sharing a smoke w/negativity
Posts: 524
Default Re: my math must be flawed, cuz this doesnt sound right

[ QUOTE ]
That does not make mathematical sense

[/ QUOTE ]
I agree, that's why I fixed your calculation.

[ QUOTE ]
You are inflating the results

[/ QUOTE ]
No, I'm deflating them, from your inflated figure.

Edit: And actually, this doesn't even factor in the fact that you want only hands where one player has them, it just removes the double counting of the times when two people have A-A.
Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -4. The time now is 10:54 AM.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.