The question isn't:

"how many rolls do we need so that I have a >50% chance of seeing a streak of length L or longer",

or

"how many rolls do we need so that the expected longest streak is of length L".

The question is:

"we have seen N rolls, what is my chance of seeing a streak of length L or longer?"

Which is kind of the same thing, but in the opposite direction, and apparently much harder to calculate.

He means that time will tell which of your victims end up losing and which get lucky - not that time will tell whether anyone loses or not.  That is already a foregone conclusion.

He was on Just-Dice today.

He deposited 20 BTC to an account, and it was withdrawn shortly afterwards.

He says he didn't withdraw it, and that there's no possible way his machine has malware on it, so it must be a Just-Dice bug.


I understand he has a dice site of his own.

If you wanna make money now, invest with something that isn't run by a scammer.

If not, there's always a new "double your money" scam.  Once this one blows up another one will replace it.

I hesitate to mention this, but if you carefully pick your martingale strategy it is more effective than a single large bet at achieving your goal (whatever that goal is).

I'm not upset, I'm just pointing out that this is a scam.

OP claims:


This isn't true.  It can't be true.  OP doesn't have enough coins to double any amount with no upper limit.

This is "ground to stand on".

It can work for quite a long time if you're lucky enough.  If you keep doing it long enough you'll lose, just like with any other strategy.  But you can't say it will never work.


I'm not sure that's true.  When you take into account the fees that your broker takes, and the fact that you're effectively competing against people with inside knowledge, you might find that you get better odds playing at a low edge casino than taking on the sharks at the stock exchange.  I would say that for an inexperienced player the odds are worse picking stocks than they are rolling dice.

But you said "educated".  In that case it depends what kind of education you have.  If you know which stock is about to move where, then sure...

The reason they all bail in the end is because there's no way they can keep up with the payments.

The kinds of daily interest these schemes pay is impossible to keep up.  The only way they pay you is from deposits made by new victims.  And they need exponentially increasing levels of new investment to keep it going.

Exponential growth isn't possible, especially when there is a fixed amount of BTC in the world, and so the scheme inevitably collapses.

Even if the guy running the scheme plays by the rules, and only takes a small percentage for himself, he still won't be able to keep it going for long until he runs out of coins to pay you with.  And as he has demonstrated by lying in his trust feedback about me, he doesn't play by the rules.  I would advise you not to get involved.

... and was given it:

The expected number of rolls R(N) to get a streak of length N where each roll has probability p is:

R(0) = 0
R(N) = (R(N-1)+1)/p

I tested this via simulation and it does appear to be true.

That gives these expected numbers of rolls for these streak lengths of losing 49.5% rolls (p = 0.505):


Also, using simulation, I tried to figure out the number of rolls you need to make to have a 50% chance of seeing a streak of length N.  It looks to me like the number is about sqrt(2) times smaller than the above numbers, and so we need to have seen 410M/sqrt(2) = 290M rolls to have a 50% chance of seeing a streak of length 28.

Since we've seen 357M rolls, we presumably have a greater than 50% chance of seeing such a streak.

This is pretty low quality research I did using simulation.  The sqrt(2) thing in particular is very dodgy.

Try emailing support@coinroll.com

I didn't expect you to abuse the trust system by posting a groundless accusation as an act of revenge.

In your libellous trust rating of me you used a different Ponzi scheme that I have called out as a reference.  It is nothing to do with me.

If you're going to keep accusing me of running a Ponzi scheme I am going to keep defending myself.

I don't run a Ponzi scheme and never have, while you are running one in this very thread.

If you have any evidence that your claims are true, please present it.  But of course you won't, because there isn't any.

I will continue to warn potential victims of the scam you are running here.

OK, still too easy for the player.  What if we don't let them cash out until they've made a million bets, and still only let them start with enough to make a single bet?

Still no good.  It takes a few more players before one goes to the moon, but it still happens, and when it does he breaks the bank:

OK, so let's give the casino a better chance.  Each player starts with just $25, and has to flat-bet $25 over and over until they either bust or make 1000 bets.

Now the casino is bound to win, right?

Wrong:

OK, maybe I misunderstood your specification, but here are the results:

I coded a simulation, ran it 6 times.  The first time I ran it the first player busted and the 2nd player made 1000 bets without busting.  The other 5 times the first player made 1000 bets without busting:


Here's the simulation code:

I'll run that simulation and let you know how it goes.

It seems your reaction to me calling your Ponzi a Ponzi was to post this on my trust:


Are you claiming you aren't running a Ponzi?  If so, how are you generating such amazing returns for your victims customers?  Of course you have had "issues" on this account yet.  That's how Ponzi schemes work.  You pay out in the beginning, then stop when you can no longer afford the payouts.  Then you make a new account and start again.  Do you think people are stupid?

And what makes you say I'm running a Ponzi?  I can demonstrate the source of the profits my customers make.  Can you?

If you want to win 1 BTC, you could:

a) risk 0.1 BTC at 9% for an 11x payout, or you could
b) risk 10 BTC at 90% for a 1.1x payout.

In each case you expect to lose 1% of the amount you risk, so b) costs about 100 times more than a) in terms of the amount you expect to lose, while only having a 10 times better chance of success.

That makes 90% seem like a bad deal compared to 9%, even though they both have a 1% edge.

Does that make sense?

I would suggest exactly the opposite.

all new gaming sites that employ a system like this should be avoided until they correct this obviously bad practice

It's like this:

PrimeDice: changes secret every roll - makes the user have to do much work to verify (too hot)
CoinRoll: changes secret once per day - makes the user wait too long to verify (too cold)
Just-Dice: changes secret when the user asks to change it (just right)

It's like Goldilocks up in here.

Maybe consider the risk of losing half the bankroll - a kind of a 'half life' thing.

Also, what if someone came with enough coins to bet the maximum at 98% over and over.  Each time they have a very good chance of winning 0.5% of the house bankroll.

If they win 138 times in a row, they've won half the bankroll, and they can do so with 6% chance:

>>> 0.995 ** 138 = 0.5007
>>> 0.98 ** 138 = 0.06154

If the max profit per roll was a full 1% of the bankroll, they only need to win 69 times in a row, and they can do so with 25% chance:

>>> 0.99 ** 69 = 0.4998
>>> 0.98 ** 69 = 0.24808

So by cutting the max profit from 1% to 0.5% we've made it ~4 times harder to win half the bankroll by max-betting at 98%.