In normative decision theory, the weight of an uncertain event in a decision is governed solely by the probability of the event. A large body of empirical research suggests that a single notion of probability does not accurately capture peoples' reactions to uncertainty. As early as the 1920s, Knight made the distinction between cases where probabilities are known and where probabilities are unknown. We distinguish another case –- the unknowable uncertainty –- where the missing information is unavailable to all. We (...) propose that missing information influences the attractiveness of a bet contingent upon an uncertain event, especially when the information is available to someone else. We demonstrate that the unknowable uncertainty –- falls in preference somewhere in between the known and the known uncertainty. (shrink)

I examine the foundations of a just society using the lens of decision theory. The conception of just society is from an individual’s viewpoint: where would I rather live if I have an equal chance of being any individual? Three alternative designs for a just society are examined. These are: laissez-faire, maximin and social minimum. Two assumptions about human nature clarify the distinction among three societies. The first assumption is that a representative individual’s utility function is concave. The second assumption (...) recognizes that redistribution to achieve equality reduces total wealth. A rational individual would prefer a society where one is free to maximize one’s expected utility. A social minimum that includes both the provision of essential human needs and equality of opportunity (education, healthcare, access to capital) for a flourishing life emerges as a candidate solution for the basic structure of society. (shrink)

For decisions whose consequences accrue over time, there are several possible techniques to compute total utility. One is to discount utilities of future consequences at some appropriate rate. The second is to discount per-period certainty equivalents. And the third is to compute net present values (NPVs) of various possible streams and to then apply the utility function to these net present values. We find that the best approach is to first compute NPVs of various possible income streams and then take (...) the utility of such NPVs. We show the drawbacks of other alternative models of evaluating income streams. The article discusses the advantages of the power and logarithmic forms in the modeling of time preference. These are the only forms for which utility of income and utility of consumption are strategically equivalent. Further, these forms permit the flexibility in the choice of a time period (e.g., monthly or quarterly) without modifying the utility function, thus simplifying analysis. (shrink)