Want to know about Provably fair...

[Crossbow376]

So don't worry, casinos will never bankrupt (as long as they have active players)

The house edge would bring profits to the house in the long term, but the house could lose in the short term.
And so casinos need to set the max win correctly (for example, using Kelly formula).

[Wusolini]

I see some gambling sites mention that they are provably fair. They provide some seed and ask to check some hash or whatever. My question is, can this fairness really be checked from outside ? Where are they twisting to make sure the house's win ?

Yes, it can.
.....

P.S. This's only principle, and can be used in various way. You should check description on particular site.

Thanks wusolini, you explained very well, I also always thought how probably fair work.

You're welcome.

I see some gambling sites mention that they are provably fair. They provide some seed and ask to check some hash or whatever. My question is, can this fairness really be checked from outside ? Where are they twisting to make sure the house's win ?

Yes, it can.

.....

That is an awesome explanation. I wonder how the house make sure that they win in the long term ? Do they really gamble with the user choice ?

I'm glad you understand, I've tried to make it in simple.

there is always a some formula, that guarantees long time profit to operator. And if not, it can be just adapted  . So don't worry, casinos will never bankrupt (as long as they have active players)

So, do u mean, the program inside is rigged for the long run that make sure the house will always win ?

Not rigged, but calculated. It's all about math and likelihood
something like: unlikely you win , even more unlikely you win a jackpot and likely you loose, but most likely the game wins.

But it's a different story, the game is still provably (you can check it) fair (result is random or known ahead or ... )
well calculated game don't need to cheat, just need to sustain as long and get as much players as possible    

So don't worry, casinos will never bankrupt (as long as they have active players)

The house edge would bring profits to the house in the long term, but the house could lose in the short term.
And so casinos need to set the max win correctly (for example, using Kelly formula).

Thanks for pointing out Kelly formula  ... it's all about math

[BitCoinDream]

I understood the grid example. But, I wonder how a dice game can be provably fair, because we may verify SHA256 of the amount that will come after roll beforehand. But, how to know, that this amount is itself not rigged, i.e. while playing a high roller where the amount needs to be more than 75, if the system takes the amount as 67, player will always lose. Am I missing something ?