Re: What would make you believe?

Erik Max Francis <max@xxxxxxxxxxx> wrote:
mcv wrote:
Erik Max Francis <max@xxxxxxxxxxx> wrote:
mcv wrote:

Then consider this: with a $65 million jackpot and $1 tickers, chances
of winning the jackpot are less then 1/65 million.
No, depends on how many people play, and what distribution of numbers
they choose.

If the chance is not less than 1/65 million, the lottery is losing money.
Not a very smart way to run a lottery.

If every drawing worked that way, yes. Lotteries with progressive
jackpots don't work that way, however, since the jackpot increases if no
one hits their numbers. The probability of someone hitting their
numbers (or more than one person hitting their numbers) depends on the
distribution of lottery number picks (people aren't random so the
distribution is not either), and how many people play.

Under some circumstances, the probability of you winning times the
expected jackpot payout can be _more_ than the price of a ticket, making
it positive expectation. It only happens when there are large jackpots
(further complicated by the fact that when the jackpot is large, more
people play, which is actually a rational decision), and the positive
expectation isn't _much_ over the price of a ticket, but it happens.

I once heard that Voltaire made a small fortune that way. He figured
out that the jackpot of the Paris lottery was bigger than the cost of
all tickets put together, so he and his friends bought all tickets
and won. No idea if it's really true, but if it is, I'm sure people
would try to duplicate that trick if the opportunity arose again.

But you've just made up different numbers here. Make up different
numbers, and it's _less_ likely you'll win, not more. This isn't an
argument because you're just plugging in numbers that will give you the
result you want.

How do *you* estimate the chance that some completely bizarre story
that completely conflicts with your worldview is actually true? I'm
always open to the possibility that my worldview is completely wrong,
and if someone cares enough to come and tell me that story in person,
I'm certainly willing to grant him a chance of one in a million that
he's right. At worst, my chances of winning the lottery are unchanged,
at best, they might be significantly increased.

One in a million is vastly too favorable. Consider that his story is
true. That he's a time traveller come back in time to get someone to
buy a lottery ticket seems unlikely enough. What's the chance that he's
done that _and he's selected you for the task_? There are currently
three hundred million people in the United States, for instance. What's
the chances that he'd select me randomly (and it is effectively random;
he may know that I'm some big part of future history that he's trying to
change, but I sure don't).

Ofcourse, as long as he hasn't picked anyone yet, it's ludricrous to
think that he'd pick me. But people don't show up at my door with this
sort of story every day (perhaps I live in an unusually sane
neighbourhood), so when someone does show up with this story, I'm not
comparing the chance that he picks me to the chance he picks someone
else, but the chance that he tells me this story to the chance that
someone else is telling me that story.

And not a lot of people tell me stories like that. Ofcourse when it
happens, the obvious conclusion is still that he's insane, but the
chance that he's telling the truth, given that it's possible and
given that someone at my door is telling me this story, is a lot
bigger than the chance that he picks my door, only given that it's
possible.

Would throwing math at this help? It's been a while, but I did learn
the math for this sort of thing once. And it's not really that hard,
it's just something you need to get your head around.

People are very bad at estimating risk, and this is just another example
of that.

People are also very bad at related chances, and this also happens to
be an example of that. Ofcourse it could easily be that my estimates
are way off. And more importantly, big parts of the eastimates are
completely unknowable. How can you possibly put a probability to the
possibility that time travel is possible? You can't. You *can*
calculate chances of winning the lottery, or chances of someone
picking a certain door. But in order to know what the chance is that
someone with an outlandish story at my door is telling the truth, you
need to know how many people who come to my dooor with such a story
are telling the truth, and how many aren't. And you can't know that.
you think millions of people come to my (or any) door with such
stories, I think not.

There is no chance that such an unlikely story will significantly
reduce my chances of winning the lottery, because there's still the
(estimated) 0.999999 chance that he's a nutcase and my lottery ticket
will have the same chance of winning as every other. If he predicts
a sure loser, that will reduce my chances of winning the lottery by
0.000001 * 0.00000001 = 0.00000000000001. I'm really not going to
worry about that.

But there are other considerations you're not taking into account. If
the lottery ticket does hit, then the chances are far more likely that
you are (unwittingly) involved with something nefarious than that his
story is true. It's more likely that you're a patsy, or an identity
theft target, or are going to be threatened and blackmailed for the rest
of your life.

I disagree. At least, I disagree that it's more likely for me than for
any other lottery winner. I know too little about lotteries to know
whether winners are publicly announced or kept secret, but if it's
secret, he won't know if I won, and me buying the ticket or not will
have no influence on him blackmailing or threatening me, and if it's
public, other winners are just as public too, and he could have
treatened and blackmailed them without going to all the trouble of
rigging the lottery.

The only way this would make sense, is if he has access to resources
that are only useful for blackmailing or threatening me specifically,
and not the vast majority of other people in the world, and I just
don't see what that could be. I don't have any $65 million secrets
as far as I know.

Even if he's just plain crazy and his lottery ticket _doesn't_ hit, the
chances that he'll come back and want his cut for money you didn't get
(because he's crazy and can't be convinced otherwise) is surely vastly
more likely than hitting the lottery on your own.

But me not buying the ticket won't make a difference there. He might
even become more angry at me if I didn't buy the ticket.

If you estimate the chance that he does know what he's talking about
much smaller than the chance of winning the lottery, then it's just
a regular lottery ticket with the same tiny chance of winning as
every other. The only way my chance of winning the lottery can be
reduced by listening to this guy is if the chance of him knowing
what he's talking about (and lying about it) is very close to 1.

If you want to increase your chances of winning the lottery, buy two
tickets. That will vastly increase your chances of winning compared to
honoring this guy's request.

That'd just double the chance of winning. And double my loss. Not a big
help, I'm afraid.

And you're missing an obvious third possibility: that the ticket _will_
win, but not for the reasons he's saying. His story is too outrageous
to believe, but maybe he's right for the wrong reasons. Maybe they've
rigged the lottery but are too close to the process to try to collect it
themselves and need a patsy. Maybe you'll find yourself blackmailed and
threatened for the rest of your life. Maybe you'll be murdered and
someone else will assume your identity. Maybe countless other nasty,
unpleasant things that you can't guess off the top of your head. You
don't know how likely these are, but surely they're more likely than him
really being a time traveller.

Seems rather farfetched for such a mundane scheme. If they have the power
to rig a reputable lottery, I don't see what they'd need a patsy for.
They'd seriously complicate their crime by making it depend on blackmail
or identity theft. Besides, you can blackmail and steal identities from
lottery winners without rigging the lottery.

If you can predict lottery winners, you'd better make sure the winning
ticket is bought by someone you can control, and not some complete
stranger. Considering my lack of criminal/blackmailable history, I'd
find it less likely that an organised crime ring chose me as a patsy
they can control than that some bum on my doorstep is actually from
the future.

It depends on what the scam is. Maybe you look like someone (who was
not the guy at the door) who plans to assume your identity after you win
the lottery (sorry old chap). Maybe they'll steal the money from you
and then frame you for the rigging (you will be, after all, an accomplice).

This is the first story that seems plausible. He could have an
accomplice who's practically my identical twin, and have selected me
on that basis. It still sounds unnecessarily complicated compared to
simply buying the ticket themselves. Besides, if they can steal my
identity with impunity, they can still do that when I don't buy the
ticket.

The point is, the story is so ridiculously suspicious that it would be
foolish to accept it. That goes for whether you're thinking about the
seriousness of his story, or are concerned about what is really going on
here.

The story is ridiculous, weird and unlikely, but I still disagree with
the suspiciousness of the story. Maybe I'm just not paranoid enough.
Or perhaps, when an event like this really happened to me, I would
suddenly become paranoid and decide not to buy the ticket.

If he and his colleagues have rigged the lottery and given you the
winning numbers and told you to buy a ticket, you're an accomplice.

I don't see how. I know nothing about the rigging of the lottery and I
don't know any of the riggers. All I know is that some bum told me a
bizarre story and I decided to buy a ticket just for laughs.

Yeah, try telling that to the prosecutor. I'm sure _he_ will estimate
the probability of your story as being a lot less than the probability
of you being involved.

That still doesn't prove my guilt. No doubt being prosecuted will suck,
but at least I'll have millions to pay for my defense. Or after being
presented with proof that the lottery was rigged by criminals, I can
simply return the money like any good citizen would do. Unless ofcourse
the criminals steal my money, but if they need to steal my money to get
to it, and leave me with nothing, how involved can I really have been?
That just supports my story that I had nothing to do with it.

And, as I point out above, there are other, more sinister, possibilities
you'd have to consider.

But you're only looking at it from my point of view, and not from the
criminals' point of view. Why the hell would they even need a patsy,
and why would they choose me for it? It's their motives that don't
make sense, and that has nothing to do with the physical possibility.

You do realize precisely that same reasoning applies to evaluating the
truth of the guy's story, right?

The point is, you _don't_ know. However, the scenarios in which the
riggers want to distance themselves from their crime and collect their
proceeds through other means by bringing in a total stranger who doesn't
know them from Adam is vastly more likely than a time traveller knocking
on your door and telling you the winning lottery ticket.

Could be. I consider them both too unlikely to worry much about it.


mcv.
--
Science is not the be-all and end-all of human existence. It's a tool.
A very powerful tool, but not the only tool. And if only that which
could be verified scientifically was considered real, then nearly all
of human experience would be not-real. -- Zachriel
.

Quantcast