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Gravity Model Estimation: Fixed Effects vs. Random Intercept Poisson Pseudo Maximum Likelihood

ABSTRACT The standard Anderson and van Wincoop gravity model has typically been estimated using a fixed-effects approach. However, a fixed-effects approach has a major drawback: it does not allow for the estimation of exporter- and importer-invariant variables. Thus, at least in a cross-sectional context, economically relevant variables such as exporter and importer gross domestic product are disregarded. We propose a random intercept model to address this gap. For large datasets, this approach not only provides identical estimates like a fixed-effects approach, but also allows for the estimation of exporter- and importer-invariant variables.

The Ethics of Financial Speculation in Futures Markets

This article sketches an ethics of (financial) speculation in futures markets. (1) It identifies an intentionalistic fallacy prevalent in moral criticisms of speculation in general and of financial speculation in particular. (2) It scrutinizes the degree to which the recent debate on financial speculation with agricultural commodities follows the general pattern of moral criticism and its intentionalistic fallacy. (3) It then provides a theoretical and empirical in-depth analysis of long-only index funds engagement in futures markets and concludes that moral criticisms which put them in the pillory as “hungermakers” are unjust(ified). This proves that ethics, understood as a theory of morality, can criticize moral criticisms of financial speculation on moral grounds. (4) Finally, this article discusses the option of interdisciplinary cooperation between ethics and economics.

Preference Erosion – The Case of Everything But Arms and Sugar

While the European Unions Everything But Arms (EBA) agreement has granted unlimited preferential access to the European market for the least developed countries (LDCs) since 2001, the sugar sector has been exempted for the first years. Only from 2009 on, the LDCs were entitled to export an unlimited amount of sugar to the EU, receiving the intervention price. The expected increase in sugar imports led the EU to substantially reduce the intervention price, besides other measures. This caused a disadvantage for countries which had been granted preferential access to the European market already: the African, Caribbean, and Pacific (ACP) countries. Our paper quantifies this erosion of preferences, employing a gravity framework. In terms of methodology we are addressing two fundamental problems well known in the gravity literature. The occurrence of excess zeros in the dependent variable of such disaggregated data is tackled with the employment of the scale‐independent negative binomial quasi generalised pseudo maximum likelihood estimator. The problem of identification is addressed by modelling the policy change with the continuous preference margin instead of using dummy variables. We find that preference erosion did occur. The ACP countries were indeed negatively affected by the consequences following the introduction of the EBA.

Are We Moving Towards Functioning Agricultural Markets and Trade Relations

We introduce a special feature on the functioning of international agricultural markets. This feature is motivated by the increased interest in the functioning of commodity markets raised by unprecedented price turbulences since 2008, major structural changes through changed roles of emerging economies and related concerns regarding food security. We argue that the delineation of non-functioning markets from markets that adequately adjusted to adverse framework conditions lacks theoretical foundation. We discuss the relevance of some results on institutions for agricultural markets in emerging and transition countries. A synthesis of the articles included in the special feature is provided by highlighting the selection of topics that span a topical range covering price formation on world and domestic markets, market power and trade policy modelling.

Speculation on Agricultural Commodities: A Brief Overview

This short essay on financial speculation with agricultural commodities offers (1) a survey of the real economy factors that caused recent hunger crises, (2) an overview of academic research on the impact of index-based financial speculation on agricultural futures markets, and (3) a discussion of political measures that are appropriate for im-proving global food security. The arguments are supported by numerous graphs.