Hi guys,
I was just running a few simulations on the commercial viability of running a satoshi's dice style bitcoin gambling site. I wanted to share my results about the viability of the various different betting odds.
Assuming:
* 2% house edge
* initial bankroll of 1000 BTC
* between a random bet size between 0.01% and X% of house bankroll for each bet
Here are the results of amount of bets taken in order to reach 100% return on investment (for the developer/investor, not the player). In each case the maximum bet amount was adjusted to keep the volatility of results similar.
240/256 odds, 93.75% chance of winning, payout 1.046x, 0.01% -> 1% house bankroll bet size:
7000 bets![](https://ip.bitcointalk.org/?u=https%3A%2F%2Fi.imgur.com%2FJO586aE.png&t=671&c=bE1xBTzsKaJVbw)
200/256 odds, 78.13% chance of winning, payout 1.255x, 0.01% -> 0.5% house bankroll bet size
15,000 bets![](https://ip.bitcointalk.org/?u=https%3A%2F%2Fi.imgur.com%2FaM8ZRHq.png&t=671&c=JJ1VsLf6IBphrA)
128/256 odds, 50% chance of winning, payout 1.961x, 0.01% -> 0.1% house bankroll bet size
125,000 bets![](https://ip.bitcointalk.org/?u=https%3A%2F%2Fi.imgur.com%2Fjvh1sII.png&t=671&c=Du_wAt-8fgOf4w)
64/256 odds, 25% chance of winning, payout 3.92x, 0.01% -> 0.075% house bankroll bet size
275,000 bets![](https://ip.bitcointalk.org/?u=https%3A%2F%2Fi.imgur.com%2FRYhvy4i.png&t=671&c=rmhgIZXUkShHGg)
As you can see, the maximum allowed bet size has to reduce fairly drastically to keep volatility in check, which sends the required number of bets sky-rocketing as odds of winning decrease. Strangely counter-intuitive results.
The question is, how can sites like justdice.com, satoshiroulette.com and satoshidice.com offer odds even less than 25% and stand any chance of making their money back (considing the number of required bets) with edges less than 2%?
Cheers, Paul.