Consider the indicator gambles for various events in this scenario. Consider a choice between a bet that wins if the marble drawn is red (I), versus a bet that wins if the marble drawn is blue (II). You might prefer I to II since I involves risk while II involves ambiguity. A prospect is risky if its outcome is uncertain but its outcomes occur with known probability. A prospect is ambiguous if the outcomes occur with unknown or only partially known probabilities. Now consider a choice between a bet that wins if the marble drawn is not blue (III) versus a bet that wins if the marble drawn is not red (IV). Now it is III that is ambiguous, while IV is unambiguous but risky, and thus IV might seem better to you if you preferred risky to ambiguous prospects. Such a pattern of preferences (I preferred to II but IV preferred to III) cannot be rationalised as the choices of a precise expected utility maximiser. The gambles are summarised in the table.