Two Plus Two Older Archives  

Go Back   Two Plus Two Older Archives > General Gambling > Probability
FAQ Community Calendar Today's Posts Search

 
 
Thread Tools Display Modes
Prev Previous Post   Next Post Next
  #1  
Old 09-14-2002, 09:04 PM
Mike Haven Mike Haven is offline
Senior Member
 
Join Date: Sep 2002
Location: Northern Ireland
Posts: 2,288
Default An interesting phenomenon.

In the 911 thread cardshark asked: "If I you roll a die, the odds of rolling, let’s say “3”, are 1/6. How about if you are about to roll the die six times, and I make a bet that you will roll “3” on the third roll; are the odds still 1/6?"

yes, is the answer

but here's an interesting one where the odds of future events can be calculated and do change (and there's a bet in it somewhere!)

if someone opened a book and pointed randomly at one letter on a page and asked you to guess whether it was a vowel or a consonant obviously you would have to bet that it was a consonant, as you know, instinctively, there are more consonants than vowels in a piece of writing (probably about 57% to 43% on average)

now, if you could talk this person into telling you what the letter before the one you have to guess was, things would change dramatically

a large study (markov's) showed that a vowel is followed by a consonant 87% of the time and a consonant is followed by a vowel 66% of the time!

hence, if you are told the previous letter was an "n" for example, you would gaze into the distance for a few seconds, and then "guess" vowel, with a 66% chance of being correct - well worth trying to get an evens bet out of your mark with such a high likelihood of your winning

here's where it gets even more interesting

because you know the percentages as above, you can calculate the chances of each of the NEXT letters being vowels or consonants!

for example, if the announced letter is an "e" what is the chance of the next-but-one letter also being a vowel?

there are only two patterns that would give this result: v-v-v and v-c-v

from our percentages above v-v-v will occur 13% x 13% = 1.7% of the time and v-c-v will occur 87% x 66% = 57.4% of the time

so the next-but-one letter to an "e" will be another vowel 1.7% + 57.4% = 59.1% of the time!

by the same type of calculations you will find that the letter three steps ahead from a vowel will be a consonant 65% of the time or three steps ahead from a consonant the letter will be a vowel 50% of the time

this could be the best bet to offer to disguise your winning strategy

every time he calls a vowel bet that the letter three steps ahead is a consonant and every time he calls a consonant call the opposite of your previous answer to make it sound like you are betting randomly (you ARE betting randomly at this point as it is an evens bet - you are making your money on the 65% consonant bet)

Reply With Quote
 


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 05:51 AM.


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