A strategy is obviously dominant if, for any deviation, at any information set where both strategies first diverge, the best outcome under the deviation is no better than the worst outcome under the dominant strategy. A mechanism is obviously strategy-proof (OSP) if it has an equilibrium in obviously dominant strategies. This has a behavioral interpretation: a strategy is obviously dominant if and only if a cognitively limited agent can recognize it as weakly dominant. It also has a classical interpretation: a choice rule is OSP-implementable if and only if it can be carried out by a social planner under a particular regime of partial commitment.

Segerstrom (1998) demonstrates that the social optimum requires “radical” technological breakthroughs to be treated less favorably than “incremental” innovations in a growing economy. The aim of this note is to assess the robustness of this welfare result on the basis of two levels of generalization: (i) the elasticity of substitution between any two goods is allowed to be larger than one, and (ii) inter-industry spillovers are introduced. We show that Segerstrom’s results can be reversed. It is also shown that in contrast to Segerstrom, R&D subsidies can be globally optimal, irrespective of the size of innovation, when inter-industry spillovers are large.

We propose an extensive-form solution concept, with players who neglect information from hypothetical events but make inferences from observed events. Our concept modifies cursed equilibrium (Eyster and Rabin 2005) and allows that players can be cursed about endogenous information.

We use a two-period matching model with initial uncertainty about productivities of participants to analyze incentives for early contracting or unraveling. Unraveling provides insurance in the absence of complete markets, but causes inefficient assignments. Unraveling is more likely the smaller the applicant pool, the smaller the proportion of more-promising applicants, and the greater the heterogeneity in the pool. Banning early contracts hurts firms and benefits lesspromising applicants; the effects on more-promising applicants depend on how the gains from early contracts are shared. Ex post buyouts eliminate inefficient assignments, and more-promising applicants always unravel.