• Decentralizability of Efficient Allocations with Heterogenous Forecasts
  Atsushi KajiiShurojit Chatterji

  Abstract

  Do price forecasts of rational economic agents need to coincide in perfectly competitive complete markets in order for markets to allocate resources efficiently? To address this question, we define an efficient temporary equilibrium (ETE) within the framework of a two period economy. Although an ETE allocation is intertemporally efficient and is obtained by perfect competition, it can arise without the agents forecasts being coordinated on a perfect foresight price. We show that there is a one dimensional set of such Pareto efficient allocations for generic endowments.  
  

   

  Introduction

  Intertemporal trade in complete markets is known to achieve Pareto efficiency when the price forecasts of agents coincide and are correct. The usual justification for this coincidence of price forecasts is that if agents understand the market environment perfectly,  they ought to reach the same conclusions, and hence in particular, their price forecasts must coincide. But it is against the spirit of perfect competition to require that agents should understand the market environment beyond the market prices they commonly observe; we therefore study intertemporal trade without requiring that price forecasts of heterogenous agents coincide.  

   

  WP031

  2021.03

  PDFファイルはこちら

• Efficiency, Quality of Forecasts and Radner Equilibria
  Atsushi KajiiShurojit Chatterji

  Abstract

  We study a simple two period economy with no uncertainty and complete markets where agents trade based on forecasts about the second period spot price. We propose as our solution concept a set of forecasts with the following properties: there exist (heterogenous) forecasts contained in this set that lead to efficient allocations, the set contains only those forecasts that correspond to some efficient equilibrium, and finally that the forecasts assign positive probability to the actual market clearing spot price. We call such a set of prices an efficient equilibrium with ambiguity, and interpret it as a generalization of Radner equilibrium that delivers efficient allocations under forecasts that possess a self-fulfilling property that is weaker than perfect foresight. 

  Introduction

  Walrasian trade in intertemporal economies require households to forecast prices that will prevail in spot markets at future dates. The ubiquitous nancial equilibrium model that is used to address this aspect of intertemporal economies is the one proposed by Radner (1972) (following Arrow (1963)) and is the bedrock of modern treatments of general equilibrium. This resulting Radner equilibrium (henceforth, RE), postulates that households correctly anticipate all spot prices at future dates; a RE is accordingly an equilibrium with perfect foresight (henceforth, PFE), where the forecasts of heterogenous households are perfectly aligned.

   

   

  WP024

  2020.06

  PDFファイルはこちら

• Decentralizability of Efficient Allocations with Heterogenous Forecasts
  Atsushi KajiiShurojit Chatterji

  Abstract

  Do price forecasts of rational economic agents need to coincide in perfectly competitive complete markets in order for markets to allocate resources efficiently? To address this question, we define an efficient temporary equilibrium (ETE) within the framework of a two period economy. Although an ETE allocation is intertemporally efficient and is obtained by perfect competition, it can arise without the agents forecasts being coordinated on a perfect foresight price. We show that there is a one dimensional set of such Pareto efficient allocations for generic endowments.

  Introduction

  Intertemporal trade in complete markets is known to achieve Pareto efficiency when the price forecasts of agents coincide and are correct. The usual justification for this coincidence of price forecasts is that if agents understand the market environment perfectly, they ought to reach the same conclusions, and hence in particular, their forecasts must coincide. But it is against the spirit of perfect competition to require that agents should understand the market environment beyond the market prices they commonly observe; we therefore study intertemporal trade without requiring that price forecasts of heterogenous agents coincide.

   

   

  WP016

  2020.02

  PDFファイルはこちら