Hypothetical scenario:
You can bet on a single dye roll (choosing a number between 1-6), but if you win you get paid x12 of your stake (instead of x6).
So the Expected Value is positive (see example below), but you'd still have 83% chance of losing.
1 - will you take that bet?
2 - if so, what % of your available funds would you put at stake (i.e. funds you're willing to gamble and afford to lose)?
Again, this is a single, non-repetitive bet.
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Simulation for BTC1 bet:
EV = (83% x -BTC1) + (17% x BTC11) = +BTC1.04
Edit: calculation corrected, credit to Saint-loup
The x 12 that will be paid on the amount you bet is quite tempting to try. That's why it seems scary to try, especially if you bet a large amount of 1 bitcoin.
I just don't know if anyone has tried such a game, has anyone? This kind of game is only for brave gamblers who are ready to lose big money.