tournaments
Bubble factor
Also: risk premium
A number that expresses how much more losing a pot costs you than winning it gains you, in tournament equity terms. A bubble factor of 1 means chips are worth their face value (as in a cash game); on the bubble or at a final table it can be 2 or higher, meaning you need far better than even odds to call an all-in.
Example. With a bubble factor of 2 against the chip leader, she needed 67% equity to call his shove, so she folded ace-queen.
Bubble factor is the ICM idea made practical. If your bubble factor against a particular opponent is 1.5, a hand that is a 55% favourite in chips is a losing call in money. It is highest for medium stacks facing the chip leader and lowest for the chip leader facing anyone, which is the mathematical reason big stacks bully bubbles.