Definition of RoR
The RoR means the "risk of ruin" (the risk of ruin). The expression is mostly used in the world of finance among people who invest in the stock market, but also in poker. The most important element in calculating your "risk of ruin" is your winrate (your hourly rate at your limit, calculated as big blinds per 100 hands). The higher your winrate, the less likely you are to go broke. The lower your winrate, the higher your chances of ruin.
What are the elements that allow me to calculate my RoR?
The risk of ruin is mainly the variance and the rake. For example, if you have a winrate of 1bb/100 hands (which is considered low) and the rake on your board increases and you have a lot of variance, you are at risk of ruin. The elements to consider when calculating your risk of ruin are your winrate, your bankroll and the rake. There is one element missing from the equation, but it is never predictable: variance. If you are on a long unlucky streak where you earn less than your " expected value" (EV), you risk ruin if your bankroll is too small.