Uncertainty and Compound Lotteries: Calibration

The Ellsberg experiments provide an intuitive illustration that the Savage approach, which reduces subjective uncertainty to risk, is not rich enough to capture many decision makers' preferences. Recent experimental evidence suggests that decision makers reduce uncertainty to compound risk. This work presents a theoretical model of decision making in which preferences are defined on both Savage subjective acts and compound objective lotteries. Preferences are two-stage probabilistically sophisticated when the ranking of acts corresponds to a ranking of the respective compound lotteries induced by the acts through the decision maker's subjective belief. This family of preferences includes various theoretical models that have been proposed in the literature to accommodate non-neutral attitude towards ambiguity. The principle of calibration, which was used by Ramsey and de Finetti, allows an outside observer to relate preferences over acts and compound objective lotteries. If preferences abide by the calibration axioms, the evaluation of the compound lottery induced by an act through the subjective belief coincides with the evaluation of the corresponding compound objective lottery. Calibration provides the foundation that allows one to formalize and understand the tight empirical association between probabilistic sophistication and reduction of compound lotteries, for all two-stage probabilistically sophisticated preferences.

Durable Goods and Conformity

Is the variety of products supplied in markets a reflection of the diversity of consumers' preferences? In this paper, we argue that the distribution of durable goods offered in markets tends to be compressed relative to the distribution of consumers' underlying preferences. In particular, there are strong incentives for conformity in markets for durable goods. The reason for conformity is natural: durables (for example houses) are traded and as a result, demand for these goods is influenced by their resale value. Agents may like one product, but purchase another because of resale concerns. We show that (1) there is a tendency to conform to the average preference; (2) conformity depends primarily on the number of people with extreme preferences; (3) conformity increases with increases in durability, patience, and the likelihood of trade; and (4) equilibrium conformity is not necessarily optimal. Surprisingly, there tends to be too little conformity in equilibrium. Conformity also creates a demand for rental markets. Renting does not necessarily decrease conformity however. Instead, renting tends to exaggerate conformity in the owner-occupied market.

Intermediation in Innovation

The paper offers a new theoretical framework to examine the role of intermediaries between creators and potential users of new inventions. Using a model of university-industry technology transfer, we demonstrate that technology transfer offices can provide an opportunity to economize on a critical component of efficient innovation investments: the expertise to locate new, external inventions and to overcome the problem of sorting ‘profitable’ from ‘unprofitable’ ones. The findings may help explain the surge in university patenting and licensing since the Bayh-Dole Act of 1980. Furthermore, the study identifies several limitations to the potential efficiency of intermediation in innovation. ZUSAMMENFASSUNG - In diesem Papier stellen wir ein neues theoretisches Modell zur Analyse der Rolle von Intermediären zwischen Erfindern und potentiellen Nutzern von Erfindungen vor. Für den Transfer von Erfindungen aus Universitäten in den Industriebereich zeigen wir, daß Technologietransfer-Stellen den Marktteilnehmern die Möglichkeit bieten, sich die Kosten für den Aufbau der Expertise, neue externe Erfindungen zu lokalisieren und evaluieren, zu teilen. Die Ergebnisse unserer Studie können dazu beitragen, die signifikante Zunahme der Universitätspatente und - lizensen seit dem Bayh-Dole-Act von 1980 in den USA zu erklären. Darüber hinaus diskutieren wir Wohlfahrtswirkungen der Aktivität von Innovations-Intermediären.Intermediation, Market Microstructure, Matching Uncertainty, Innovation, Patent Licensing

Optimal auctions with ambiguity

A crucial assumption in the optimal auction literature has been that each bidder's valuation is known to be drawn from a single unique distribution. In this paper we relax this assumption and study the optimal auction problem when there is ambiguity about the distribution from which these valuations are drawn and where the seller or the bidder may display ambiguity aversion. We model ambiguity aversion using the maxmin expected utility model where an agent evaluates an action on the basis of the minimum expected utility over the set of priors, and then chooses the best action amongst them. We first consider the case where the bidders are ambiguity averse (and the seller is ambiguity neutral). Our first result shows that the optimal incentive compatible and individually rational mechanism must be such that for each type of bidder the minimum expected utility is attained by using the seller's prior. Using this result we show that an auction that provides full insurance to all types of bidders is always in the set of optimal auctions. In particular, when the bidders' set of priors is the ε- contamination of the seller's prior the unique optimal auction provides full insurance to bidders of all types. We also show that in general, many classical auctions, including first and second price are not the optimal mechanism (even with suitably chosen reserve prices). We next consider the case when the seller is ambiguity averse (and the bidders are ambiguity neutral). Now, the optimal auction involves the seller being perfectly insured. Hence, as long as bidders are risk and ambiguity neutral, ambiguity aversion on the part of the seller seems to play a similar role to that of risk aversion.Optimal auction, mechanism design, ambiguity, uncertainty

Willpower and the Optimal Control of Visceral Urges

Common intuition and experimental psychology suggest that the ability to self-regulate, willpower, is a depletable resource. We investigate the behavior of an agent who optimally consumes a cake (or paycheck or workload) over time and who recognizes that restraining his consumption too much would exhaust his willpower and leave him unable to manage his consumption. Unlike prior models of self-control, a model with willpower depletion can explain the increasing consumption sequences observable in high frequency data (and corresponding laboratory findings), the apparent links between unrelated self-control behaviors, and the altered economic behavior following imposition of cognitive loads. At the same time, willpower depletion provides an alternative explanation for a taste for commitment, intertemporal preference reversals, and procrastination. Accounting for willpower depletion thus provides a more unified theory of time preference. It also provides an explanation for anomalous intratemporal behaviors such as low correlations between health-related activities.

Willpower and the Optimal Control of Visceral Urges

Common intuition and experimental psychology suggest that the ability to self-regulate ("willpower") is a depletable resource. We investigate the behavior of an agent with limited willpower who optimally consumes over time an endowment of a tempting and storable consumption good or "cake". We assume that restraining consumption below the most tempting feasible rate requires willpower. Any willpower not used to regulate consumption may be valuable in controlling other urges. Willpower thus links otherwise unrelated behaviors requiring self-control. An agent with limited willpower will display apparent domain-specific time preference. Such an agent will almost never perfectly smooth his consumption, even when it is feasible to do so. Whether the agent relaxes control of his consumption over time (as experimental psychologists predict) or tightens it (as most behavioral theories predict) depends in our model on the net effect of two analytically distinct and opposing forces.willpower, self-control, hotelling

Optimal auctions with ambiguity

A crucial assumption in the optimal auction literature is that each bidder's valuation is known to be drawn from a unique distribution. In this paper we study the optimal auction problem allowing for ambiguity about the distribution of valuations. Agents may be ambiguity averse (modeled using the maxmin expected utility model of Gilboa and Schmeidler 1989.) When the bidders face more ambiguity than the seller we show that (i) given any auction, the seller can always (weakly) increase revenue by switching to an auction providing full insurance to all types of bidders, (ii) if the seller is ambiguity neutral and any prior that is close enough to the seller's prior is included in the bidders' set of priors then the optimal auction is a full insurance auction, and (iii) in general neither the first nor the second price auction is optimal (even with suitably chosen reserve prices). When the seller is ambiguity averse and the bidders are ambiguity neutral an auction that fully insures the seller is in the set of optimal mechanisms.Auctions, mechanism design, ambiguity, uncertainty

Willpower and the Optimal Control of Visceral Urges

Common intuition and experimental psychology suggest that the ability to self-regulate, willpower, is a depletable resource. We investigate the behavior of an agent who optimally consumes a cake (or paycheck or workload) over time and who recognizes that restraining his consumption too much would exhaust his willpower and leave him unable to manage his consumption. Unlike prior models of self-control, a model with willpower depletion can explain the increasing consumption sequences observable in high frequency data (and corresponding laboratory findings), the apparent links between unrelated self-control behaviors, and the altered economic behavior following imposition of cognitive loads. At the same time, willpower depletion provides an alternative explanation for a taste for commitment, intertemporal preference reversals, and procrastination. Accounting for willpower depletion thus provides a more unified theory of time preference. It also provides an explanation for anomalous intratemporal behaviors such as low correlations between health-related activities.

Stock market tournaments

We propose a new theory of suboptimal risk-taking based on contractual externalities. We examine an industry with a continuum of firms. Each firm's manager exerts costly hidden effort. The productivity of effort is subject to systematic shocks. Firms' stock prices reflect their performance relative to the industry average. In this setting, stock-based incentives cause complementarities in managerial effort choices. Externalities arise because shareholders do not internalize the impact of their incentive provision on the average effort. During booms, they over-incentivise managers, triggering a rat-race in effort exertion, resulting in excessive risk relative to the second-best. The opposite occurs during busts