Equilibria Under Knightian Price Uncertainty

• 成果类型: Article
• 署名作者: Beissner, Patrick; Riedel, Frank
• 署名单位: Australian National University; University of Bielefeld; University of Johannesburg
• 刊物名称: ECONOMETRICA
• ISSN/ISSBN: 0012-9682
• DOI: 10.3982/ECTA14934
• 发表日期: 2019
• 页码: 37-64
• 关键词: Ambiguity aversion; martingales; arbitrage; beliefs; MARKETS; rules; MODEL

摘要

We study economies with Knightian uncertainty about state prices. We introduce an equilibrium concept with sublinear prices and prove that equilibria exist under weak conditions. In general, such equilibria lead to inefficient allocations; they coincide with Arrow-Debreu equilibria if and only if the values of net trades are ambiguity-free in mean. In economies without aggregate uncertainty, inefficiencies are generic. Equilibrium allocations under price uncertainty are efficient in a constrained sense that we call uncertainty-neutral efficient. Arrow-Debreu equilibria turn out to be non-robust with respect to the introduction of Knightian uncertainty.