Constructive Decision Theory

Contemporary approaches to decision making describe a decision problem by sets of states and outcomes, and a rich set of acts: functions from states to outcomes over which the decision maker (DM) has preferences. Real problems do not come so equipped. It is often unclear what the state and outcome spaces would be. We present an alternative foundation for decision making, in which the primitive objects of choice are syntactic programs. We show that if the DM's preference relation on objects of choice satisfies appropriate axioms, then we can find states, outcomes, and an embedding of the programs into Savage acts such that preferences can be represented by EU in the Savage framework. A modeler can test for SEU behavior without having access to the subjective states and outcomes. We illustrate the power of our approach by showing that it can represent DMs who are subject to framing effects.Decision theory, subjective expected utility, behavioral anomalies

Decision-Making with Belief Functions: a Review

Approaches to decision-making under uncertainty in the belief function framework are reviewed. Most methods are shown to blend criteria for decision under ignorance with the maximum expected utility principle of Bayesian decision theory. A distinction is made between methods that construct a complete preference relation among acts, and those that allow incomparability of some acts due to lack of information. Methods developed in the imprecise probability framework are applicable in the Dempster-Shafer context and are also reviewed. Shafer's constructive decision theory, which substitutes the notion of goal for that of utility, is described and contrasted with other approaches. The paper ends by pointing out the need to carry out deeper investigation of fundamental issues related to decision-making with belief functions and to assess the descriptive, normative and prescriptive values of the different approaches

An externalist decision theory for a pragmatic epistemology

In recent years, some epistemologists have argued that practical factors can make the difference between knowledge and mere true belief. While proponents of this pragmatic thesis have proposed necessary and sufficient conditions for knowledge, it is striking that they have failed to address Gettier cases. As a result, the proposed analyses of knowledge are either lacking explanatory power or susceptible to counterexamples. Gettier cases are also worth reflecting on because they raise foundational questions for the pragmatist. Underlying these challenges is the fact that pragmatic epistemologies not only rely upon normative theories of rational choice but also require externalist standards to rule out epistemic luck. Unfortunately, we lack adequate externalist theories of rational choice. In response, I address these foundational challenges by offering the outlines of an externalist decision theory. While this task is an ambitious one that I cannot hope to complete, I survey the outlines of a decision-theoretic framework on which a richer pragmatic epistemology can be developed. My hope is that this framework opens up new avenues of exploration for the pragmatic epistemologist

A Matter of Interpretation: Bargaining over Ambiguous Contracts

We present a formal treatment of contracting in the face of ambiguity. The central idea is that boundedly rational individuals will not always interpret the same situation in the same way. More specifically, even with well defined contracts, the precise actions to be taken by each party to the contract might be disputable. Taking this potential for dispute into account, we analyze the effects of ambiguity on contracting. We find that risk averse agents will engage in ambiguous contracts for risk sharing reasons. We provide an application where ambiguity motivates the use of a liquidated damages contract.ambiguity, bounded rationality, expected uncertain utility, incomplete contracts, liquidated damages.

Revealed Unawareness

I develop awareness-dependent subjective expected utility by taking unawareness structures introduced in Heifetz, Meier, and Schipper (2006, 2008, 2009) as primitives in the Anscombe-Aumann approach to subjective expected utility. I observe that a decision maker is unaware of an event if and only if her choices reveal that the event is "null" and the negation of the event is "null". Moreover, I characterize "impersonal" expected utility that is behaviorally indistinguishable from awareness-dependent subject expected utility and assigns probability zero to some subsets of states that are not necessarily events. I discuss in what sense impersonal expected utility can not represent unawareness.Unawareness, awareness, unforeseen contingencies, null, zero probability, subjective expected utility, Anscombe-Aumann, small worlds, extensionality of acts, event exchangeability

Revealed Unawareness

I develop awareness-dependent subjective expected utility by taking unawareness structures introduced in Heifetz, Meier, and Schipper (2006, 2008, 2009) as primitives in the Anscombe-Aumann approach to subjective expected utility. I observe that a decision maker is unaware of an event if and only if her choices reveal that the event is "null" and the negation of the event is "null". Moreover, I characterize "impersonal" expected utility that is behaviorally indistinguishable from awareness-dependent subject expected utility and assigns probability zero to some subsets of states that are not necessarily events. I discuss in what sense impersonal expected utility can not represent unawareness.Unawareness; awareness; unforeseen contingencies; null; zero probability; subjective expected utility; Anscombe-Aumann; small worlds; extensionality of acts; event exchangeability