It has long been common to identify an agent's degrees of belief with her betting rates. Here is this betting interpretation (BI) in a nutshell: A bet on a proposition A with price C and a non-zero stake S (= the monetary prize to be won by the bettor if A is true) is said to be fair for an agent iff the latter is willing to take each side of the bet, to buy the bet as to sell it. Assuming that such a bet on A exists and that the C/S ratio is constant for different fair bets on A, this ratio is the agent's betting rate for A.
Rabinowicz, W. , Eriksson, L. (2014)., Betting interpretation and the problem of interference, in M. C. Galavotti, E. Nemeth & F. Stadler (eds.), European philosophy of science, Dordrecht, Springer, pp. 103-115.
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