Bitcoin Forum

Economy => Gambling discussion => Topic started by: iluvbitcoins on September 13, 2017, 12:51:58 AM



Title: PrimeDice Jackpot - 1 million rolls, 1 BTC loss, 1.09 BTC Jackpot
Post by: iluvbitcoins on September 13, 2017, 12:51:58 AM
The current PrimeDice Jackpot is 109BTC and growing

You win the jackpot if you roll a 77.77 twice in a row
Odds of doing that are 1 in a million (1000x1000)

Check this
https://docs.google.com/spreadsheets/d/1FnbaTeIhz_72ILF-GMCwRxeCowOpqisC5AF-C1LYvPA

You win 100% of the jackpot if you're using 0.01BTC bets, 10% if you're using 0.001BTC bets and 1% if you're using 0.0001BTC bets
I'm gonna use the last one for calcuations
I calculated how much we would lose to the house edge if we tried placing a million bets
The house edge is 1% (x1.01 win, 98% win chance)
Betting at 98% chance, you would lose 1BTC to the edge over 1 010 322 bets, if the results were exactly by the book (2% losses, 98% x1.01 wins).

If you win the jackpot, you get 1.09BTC
+ if you hit a streak of x1.01 bets, you can just stop and take the win.

You'd think that's a positive EV, but yeah, the thing we forget about is that rolling a million rolls doesn't guarantee you'll win a one in a million bet.

Let's do some math.

If chances of me losing a 1:100 bet is 99%, than losing it twice in a row is 0.99*0.99= 98% and three times in a row 0.99*0.99*0.99=97%.
Doing this a hundred times will yield a 36% chance of losing, which means we have a 64% chance of winning.
Same would be for rolling a million times at one in a million chances.

Which isn't really a positive EV, it's really far actually, it's a x1.1 win on a 64% chance bet, is it worth it?
Perhaps, because you can get some wins along the way, and if you're negative, hope for the jackpot.
We'll have a positive EV for the jackpot, excluding the chance you might get a lucky x1.01 streak and withdraw, solely based on the jackpot when it reaches some 160BTC .
If I did something wrong, comment below.