Dynamic directed search

摘要

The directed search model (Peters 52(5): 1117-1127, 1984) is static; its dynamic extensions typically restrict strategies, often assuming price or match commitments. We lift such restrictions to study equilibrium when search can be directed over time, without constraints and at no cost. In equilibrium, trade frictions arise endogenously, and price commitments, if they do exist, are self-enforcing. In contrast to the typical model, there exists a continuum of equilibria that exhibit trade frictions. These equilibria support any price above the static price, including monopoly pricing in arbitrarily large markets. Dispersion in posted prices can naturally arise as temporary or permanent phenomenon despite the absence of preexisting heterogeneity.