Uses of Bayesian Probability Models in Game Theory

Operationally, we can distinguish between objective and subjective probabilities as follows. Some probabilities are assigned the same numerical values by virtually all expert observers: for example, virtually all experts will agree that a fair coin will show either side with the same probability 1/2; or that a fair die will show any one of its six sides with the same probability 1/6; etc. Other probabilities will typically be assessed differently by different people: for example, different experts on horse racing will usually assign different numerical probabilities to a particular horse coming in first in a given race. Probabilities of the former type may be called objective probabilities, while those of the latter type may be called subjective probabilities.