Impact is not just volatility

With a simple scaling argument we show empirically that impact growing as the square-root of trading volume has nothing to do with diffusion price changes growing as the square root of time     

Random walks,liquidity molasses and critical response in financial markets

Stock prices are observed to be random walks in time despite a strong, long-term memory in the signs of trades (buys or sells). Lillo and Farmer have recently suggested that these correlations are compensated by opposite long-ranged fluctuations in liquidity, with an otherwise permanent market impact, challenging the scenario proposed in Quantitative Finance, 2004, 4, 176, where the impact is instead transient, with a power-law decay in time. The exponent of this decay is precisely tuned to a critical value, ensuring simultaneously that prices are diffusive on long time scales and that the impact function is nearly lag independent. We provide new analysis of empirical data that confirm and make more precise our previous claims. We show that the power-law decay of the bare impact function comes both from an excess flow of limit order opposite to the market order flow, and to a systematic anti-correlation of the bid–ask motion between trades, two effects that create a ‘liquidity molasses’ which dampens market volatility.     

Existence of marginal pricing equilibria in economies with externalities and non-convexities

We consider a general equilibrium model with externalities and non-convexities in production. The consumption sets, the preferences of the consumers and the production possibilities are represented by set-valued mappings to take into account possibility of external effects. There is no convexity assumption on the correspondences of production. We propose a definition of the marginal pricing rule, which generalizes the one used in the model without externality and, which satisfies a continuity assumption with respect to the external effect.We prove the existence of general equilibria under assumptions which allow us to encompass together the works on economies with externalities and convex conditional production sets, and those on marginal pricing equilibria in economies without externalities. We provide examples to illustrate the definition of the marginal pricing rule and to show the difference with the standard case.     

Sociological explanation and mixed methods: the example of the Titanic

Quality & Quantity - The question of how and with what methods the social sciences should explain phenomena is fiercely contested. While several scholars have argued that mixed methods may help...     

A Note on Imitation-Based Competition in Common-Pool Resources

The Tragedy of the Commons refers to the dissipation of common ressources when several appropriators have access to it. The Nash equilibrium in common-pool resource games describes such an overexploitation phenomena. However, some empirical facts and experimental results suggest that the degradation may exceed the Nash equilibrium prediction. Rapid exhaustion of resources can then be explained by learning processes based on imitation behavior. Indeed, when the number of players is limited, the evolutionary outcome implies a higher level of dissipation than the Nash equilibrium.     

Biases in Calculating Dumping Margins: The Case of Cyclical Products

A dumping investigation involves comparing export prices with a normal value loosely defined as the price in the exporter's domestic market observed in the course of normal trade. However, domestic sales with prices below production costs are excluded from the computation of a normal value. The paper illustrates how price cycles affect the magnitude of estimated dumping margins. The empirical analysis focuses on Canadian hog exports to the United States and U.S. potato exports to Canada. The estimated period and amplitude of each price cycles result in average dumping margins for Canadian hogs and U.S. potato exports of 11.5% and 5.9%, respectively. Biases in dumping margins depend on the nature of the cycle, the period of investigation, and the average production cost estimate.     

Are exports a monotonic function of exchange rate volatility? Evidence from disaggregated pork exports

Abstract.  Production and marketing lags in agri-food supply chains often force agricultural producers and food processors to commit to output targets before prices and exchange rates are realized. A theoretical model illustrates how the processor's degree of risk aversion and domestic sales may cause the relationship between volatility of the exchange rate and exports to be non-monotonic. The relationship between exchange rate volatility and Quebec pork exports to the United States and Japan is investigated using linear and non-linear estimation methods. The results support the hypothesis that the relationship between exports and volatility is non-monotonic.     

Intertemporal substitution in consumption, labor supply elasticity and sunspot fluctuations in continuous-time models

The aim of this paper is to discuss the roles of the elasticity of intertemporal substitution in consumption and the elasticity of the labor supply on the local determinacy properties of the steady state in a two-sector economy with constant elasticity of substitution technologies and sector-specific externalities. Our main results provide necessary and sufficient conditions for local indeterminacy. First, we show that the consumption good sector needs to be capital intensive at the private level and labor intensive at the social level. Second, we prove that under this capital intensity configuration, the existence of sunspot fluctuations is obtained if and only if the elasticity of intertemporal substitution in consumption is large enough but the elasticity of the labor supply is low enough. In particular, we will show on the one hand that when the labor supply is infinitely elastic, the steady state is always saddle-point stable, and on the other hand that when the elasticity of intertemporal substitution in consumption is infinite, labor does not have any influence on the local stability properties of the equilibrium path.