Your “that’s what they were carrying” remark is exactly my point. If it’s a totally random guess why not go for higher amounts? 53 cents? Why bother unless you know for certain that you’re correct or at least that the odds are heavily in your favor?
By the way, it would be 1 in 100 not 1 in one million. Actually, 1 in 99 assuming she’s not going to guess zero. Those still aren’t very good odds and 2 correct guesses are pretty remarkable.
I’ve been going back and forth on whether or not these are lucky guesses, simply good guesses where she knows how to tilt the odds in her favor, or some 100% right all the time trick.
I’m tending towards the idea that she’s using some math or something to choose likely amounts. The coffee shop incident sounds like she may have looked at their purchases and figured their change based on that. Hilarity indicates that she usually has some change in her purse and the change from a purchase would simply be added to that, likely confounding any change calculating trick. However, the fact that she had a small amount like 31 cents makes me think that it may have been the change from her drink purchase.
As for the first incident she says she hadn’t made any cash transactions. Maybe there’s more than one technique involved here. Maybe the lady bases her guesses on obvious purchases, like coffee, when she can, and uses the default amount of 85 cents when she can’t because it’s mathematically more likely, or the largest of equally likely amounts. Of course that takes us back to the question of why she would keep the guess under a dollar.
Oh, I’m nearly certain stage magicians are doing another trick, I never said otherwise.
Hilarity seems to be pretty certain about the amounts. Certain enough that she’s puzzled by the incident. I think the fact that the beggar asks for small amounts may be evidence that there is some trick that generally depends on small amounts. If she’s making totally random guesses than why not go for $1 or $2 rather than 53 cents?
I’m not following your logic. Where are these higher amounts? Other people in the parking lot? Maybe there were none. Maybe she was hitting them up too. Now if she could tell how much someone had from far away, she’d be going after the richer payoffs first. Then again maybe experience tells her that people are more willing to give away small amounts than large amounts, so she goes after the smaller, surer payouts.
That’s assuming that she can tell from far away how much someone has. It seems more likely to me that she has to interact with someone before she can perform her trick.
It would be 1 in 100 the first time. The second time it would be 1 in 100 yet again. That’s not 2 in 200, that’s 1 in 10,000. A third time makes it a million. That is, if the goal is to win three times consecutively.
The chance of an American holding much more than a dollar in change is low. We Canadians have 1 and 2 dollar coins, so its considerably more likely: almost certain in fact.
Which goes against the claim people are making that pocket change is the result of numerous transactions. If it’s not then you can guess based on obvious recent purchases.
That said, if a woman lets her change accumulate in a purse from day to day then she could easily be carrying a few dollars worth of change. It’s a different story for us guys.
Is anyone interested in a guaranteed method to double your chances of winning the lottery? I mean it, guaranteed. 100% refund if it doesn’t double your chances of winning the lottery.
Really? People just let change accumulate? I spend mine. It can fluctuate pretty wildly the course of the day.
Today I started out with 93 cents. I bought something and gave the cashier some bills and a quarter. She gave me a nickel back. So then I had 73 cents. Later I bought something with bills and got back 50 cents, putting me at 1.23. Then I bought something for 85 cents, leaving me with 38 cents.
So I’m all over the board with it.
(If it weren’t for this thread, I’d have no idea how much I have.)
I’m not making myself clear. Let me try to formalize the logic somewhat.
First, we totally throw out the idea that she’s in any way psychic. This is the real world here.
[ol][li]Assume she’s making random guesses with no method or math of any kind and that any guess, in a reasonable range, is as likely to be correct as any other. She simply makes her money off of the lucky guesses plus the “it’s already in my hand” people.[/li][li]The “already in the hand people” aren’t a sure thing. In fact, it seems intuitive to me that this will pay off less often than the correct guesses.[/li][li]She will occasionally guess right, just by sheer chance due to the number of guesses a day. These correct guesses pay off nearly 100% of the time.[/li][*]If all reasonable guesses are correct 1% of the time than a hundred guesses of 85 cents will yield 85 cents, but a hundred guesses of $1.15 will yield $1.15. So why would you go around guessing 85 cents instead of going around guessing $1.15? The only reason I can see for guessing a lower amount is because she has some way of knowing that that is the amount that that particular mark is likely to be carrying.[/ol]That’s the whole point of the argument. The only way her behavior is rational is if she has some method beyond random guessing. Of course that assumes she is rational, which isn’t a foregone conclusion.
[ol][li]Assume she’s making random guesses with no method or math of any kind and that any guess, in a reasonable range, is as likely to be correct as any other. She simply makes her money off of the lucky guesses plus the “it’s already in my hand” people.[/li][li]The “already in the hand people” aren’t a sure thing. In fact, it seems intuitive to me that this will pay off less often than the correct guesses.[/li][li]She will occasionally guess right, just by sheer chance due to the number of guesses a day. These correct guesses pay off nearly 100% of the time.[/li][li]If all reasonable guesses are correct 1% of the time than a hundred guesses of 85 cents will yield 85 cents, but a hundred guesses of $1.15 will yield $1.15. So why would you go around guessing 85 cents instead of going around guessing $1.15? The only reason I can see for guessing a lower amount is because she has some way of knowing that that is the amount that that particular mark is likely to be carrying.[/ol]That’s the whole point of the argument. The only way her behavior is rational is if she has some method beyond random guessing. Of course that assumes she is rational, which isn’t a foregone conclusion.[/li][/QUOTE]
Precisely, especially point 4.
And that one in a million is false because chance doesnt work like that in this situation. Prior successes and failures do not influence future ones. Except in that she adapts her technique.
I’m reminded of an encounter my wife and I had at a street fair a dozen years ago. This old fellow was offering to guess what day of the month you were born - within a day. Well, he got my wife and me both right, within a day. We were totally impressed - hell, to this day I’m impressed. So, jokingly, we asked the guy if he could guess the next day’s lottery. “Sure,” he says, “I’ll give you a number,” and he wrote down four digits on a piece of paper. We eagerly went off to play the number he had given us.
So the next evening, we’re watching the number being drawn on TV, and… well, you guessed it - every digit the guy wrote down was off by one.
I heard of that trick long, long ago–probably in the late 60s/early 70s. The trick is that you arrange your moves so that you are moving, then your following moves are based on the moves made by the chess masters.
Of course it would still require you to know the game and involve quite a bit of concentration. I don’t think it’s something just anybody could do.
Okay, I have no idea how I accumulate the change in my pockets. I do know that when I do laundry–and for some reason I do most of the laundry for my family–my average take is $3.36, and that never includes anything in my own pockets. Every third week or so there is a folded-up bill. The rule is that anything found in the laundry is mine.
So if I have change, it could be my laundry change. For awhile I was buying cigarettes and the usual change, for some reason, was a dime and a penny, so at any given time I was very likely to have multiple dimes and pennies; then they went up so I handed over the same amount of folding money but instead of getting back a penny and a dime, I would dig around for two pennies, or check if there were some lying on the counter.
It’s very random. If I make a cash purchase, and I think I have enough in change to make it a no-change transaction, I do it. If not, then I accumulate more change. So I might rarely have more than a dollar in change (especially if I had recently done laundry), but at that point I’d start spending it, not accumulating it.
As far as I know, there was nothing in the car or on my person to indicate the amount of change I had, nor did I actually know until I counted it out.
The amount she asked for was different when I was sitting with my friend, which surprised me. So she doesn’t just always ask for the same minimal amount.
Now it could all be coincidence. It could be that in the first instance Lady Beggar needed 83 cents to get on the bus, and I had it, and the second time she needed a different amount for a different reason, and we had that.
But it’s very mysterious, particularly the way she asked for it. I originally thought, and still think, that she had just come up with a much better schtick than merely asking for spare change, and if she guesses wrong, it probably doesn’t matter all that much.
For those who wonder why she sticks with smaller amounts, under a dollar–well, she’s a lot more likely to get that, isn’t she? Most people, once they have broken a bill, the change is just vapor. People are a lot more likely to toss small change at a beggar than folding cash.
I have been back to that parking lot many times, but never saw her again.
Oh, I have since googled Derren Brown–he’s the protege of an SDMB member? Fantastic. He was guessing how much money people had, but within a certain amount.
Lady Beggar is more impressive. She didn’t guess the whole amount–for instance, I had more than 83 cents on me, but 83 cents was all I had in change. The rest was in bills. And her guess was exact. But Brown is still pretty impressive.
(I would also really like to know how he made people forget which stop they were getting off at.)
I still think that her behavior doesn’t seem random. If she asked for 83 cents one time because she thought it was small enough that someone would part with it, then why wouldn’t she stick with amounts in the 80 - 85 range? Why later ask for 53 cents, 30 cents less, especially when it’s the total of two people’s change?
Another interesting point. When she saw two of you together she guessed the total change between you. Why? Maybe she saw the two of you sitting but couldn’t tell who had paid for which drink (or maybe one of you paid for both). Guessing the total between you is exactly the behavior I would expect in a situation where she knows how much had been spent between the two of you but was not sure who spent what.