HELP! I can’t find an column Cece wrote and I’m getting blasted by my unfaithful friends. Can anybody tell me where I can find the column?
A while back The Great One had a column that dealt with the probability in games like 3 card monty (and that insipid game show with Monty Hall). In it, he clarified that your odds of picking the correct card on the first try were, of course 1/3. However, when given the option of picking a second time, your odds were not 1/2 but actually 2/3. This caused quite a bit of consternation in subsequent columns. Cece was eventually, of course, proven correct.
Of course, that presumes you aren’t playing with somebody who is cheating you.
“The best medicine for misery is neither myth nor miracle, but naked truth.”
– Richard Walker, The Running Dogs of Loyalty: Honest Reflections on a Magical Zoo
I’m not adding anything new - just reinforcing what Rilchiam has posted. Three card monte (not to be confused w/Let’s Make A Deal) is never a straight game of chance.
I think there’s a treatment of this in one of the Big Secrets books by William Poundstone, and in some other book I read an article by Penn & Teller, describing a couple more variations (scams). - MC
You can buy a 3 card monty deck at most magic shops. But you have to ask, and they are generally pretyy expensive, around $30 bucks. The trick is that the one of the corners of two of the cards are different than the rest of that card. When you turn up the corner to show the mark, he sees, say a 6 hearts, while the rest of that same card will be ace of spades. When you flip the card, you hold your thumb over the different numbered corner. That way you never have to learn how to palm. With about a half hour of practice you can be winning money from drunks all over town.
That’s one approach, Gobucks, but rarely used on the street, because too easily uncovered.
Most 3-card monty (monte?) con artists use sleight of hand to palm cards, to make it appear they are moving a card when they aren’t, etc.
MPSIMS: When we took our son to college, we saw a guy doing a shell game on the street of the small town. There was a shill, who “won” the game as two college students watched… the shill walked off with his “winnings” and the students stepped up to try their luck. My wife and I totally cracked up; education seems to miss some of life’s basic lessons.
In any case, 3-card monte is definitely a con game, and you NEVER win unless the dealer lets you win as a come-on.
MC: “- - - I think there’s a treatment of this in one of the Big Secrets books by William Poundstone”
I think you’re right. Try the second book, Bigger Secrets. It’s the one I don’t have, but I do seem to remember reading it when I checked it out from my library.
“The day after tomorrow is the third day of the rest of your life.” -George Carlin
OK. Now that we have established that 3 card monty is a game for suckers, we can get to the heart of the matter:
A deck of cards is split into four equal piles of 13 random cards. Your goal is to turn over the 3 of hearts. (Who says the ace of spades should get all the attention…) You odds are clearly 1 in four that pile A ( or any pile) holds the 3 of hearts. If I read Cecil’s answer correctly, your odds of encountering the 3 in pile A are 1 in 4 regardless of whether you turn them over all at once or are given 13 individual chances to turn over a card. My friend insists this is not true. Am I wrong?
Would my odds change if I spread my 13 chances accross the four piles? I still maintain they do not, but as my Grandfather used to say, “Figures don’t lie, but liars sure can figure.”
AGKerr, I’m not sure I understand. If you divide the deck into four piles, of course the chances of the three of hearts being in any one pile is one-fourth. Your chances of encountering it in any one pile are one fourth.
I think the question is: If there are four piles A, B, C, and D, and I reveal cards in piles other than A, how does this affect the chances that the three of hearts is in pile A? And assuming that the cards you reveal are not the three, they surely do change that likelihood; they increase it.
Imagine the extreme and simple case where you reveal the entirety of pile B. You’re left with only three piles. If you haven’t seen the 3hearts yet, what’s the probability it’s in pile A? Why one-third, of course.
Harry Anderson also explained the monty and the some of the variations that are used to cheat. But the quote that stayed with me was “Nobody beats the Monty”. Anyone you see winning is a shill.
Harry Anderson explained the monty and the some of the variations that are used to cheat. It was in his book Harry Anderson’s games you can’t lose : a guide for suckers. But the quote that stayed with me was “Nobody beats the Monty. EVER”. Anyone you see winning is a shill.
APB says << Imagine the extreme and simple case where you reveal the entirety of pile B. You’re left with only three piles. If you haven’t seen the 3hearts yet, what’s the probability it’s in pile A? Why one-third, of course. >>
Um, no. Assuming you picked pile A to begin with, and then were shown the content of pile B (no three of hearts). The odds at which you picked pile A were 1-in-4 which are unchanged; but the odds of the the heart three being in pile C or D have now increased to 3/8th. You should switch to another pile. That’s the heart (no pun intended) of the Monty Hall problem, cited ad extremis on other threads.
