This paper proposes a model in which identical sellers of a homogenous product compete in both prices and price frames (i.e., ways to present price information). We model price framing by assuming that firms’ frame choices affect the comparability of their price offers: consumers may fail to...

In many situations a decision maker has incomplete psychological preferences, and the weak axiom of revealed preference (WARP) is often violated. In this paper we relax WARP, and replace it with convex axiom of revealed non-inferiority (CARNI). An alternative x is revealed inferior to y if x is...

This paper proposes and characterises two preference-based choice rules that allow the decision maker to choose nothing if the criteria associated with them are satisfied by no feasible alternative. Strict preferences are primitive in the first rule and weak preferences in the second. Each of...

This paper proposes a model of individual choice that does not assume completeness of the decision maker's preferences. The model helps explain in a natural way, and within a unied framework of choice in the presence of preference-incomparable options, three distinct behavioural phenomena: the...

Orthodox decision theory gives no advice to agents who hold two goods to be incommensurate in value because such agents will have incomplete preferences. According to standard treatments, rationality requires complete preferences, so such agents are irrational. Experience shows, however, that...

Modern investment theory takes it for granted that a Security Market Line (SML) is as certain as its "corresponding" Capital Market Line. (CML). However, it can be easily demonstrated that this is not the case. Knightian non-probabilistic, information gap uncertainty exists in the security...

This paper analyzes the impact of risk and ambiguity aversion - Knightian uncertainty - on the choice of optimal quality and timing of market entry. Irreversibility of the investment in product development is introduced in a continuous-time stochastic model applying the real option literature....

We analyze ecosystem management under `unmeasurable' Knightian uncertainty or ambiguity which, given the uncertainties characterizing ecosystems, might be a more appropriate framework relative to the classic risk case (measurable uncertainty). This approach is used as a formal way of modelling...