Markets and pro-poor agricultural growth: insights from livelihood and informal rural economy models in Malawi

This article presents the development of a set of programming models describing the major features of different rural livelihoods and of the informal rural economy they together make up in Malawi. The models allow for differentiated responses by different household types to change and for the partial equilibrium effects of consequent supply, demand, and price adjustments in labor and grain markets. The models provide insights into the relations between own‐farm and nonown‐farm activities in different households' livelihoods and in the informal rural economy as a whole, and are used to investigate possible impacts of increasing cash crop prices and of a more open rural economy. Impacts of these changes on the poor are found to be critically dependent upon supply and demand elasticities in labor and grain markets, but the poor could potentially suffer significant losses from increased openness of the local economy leading to increased expenditure by less poor households on imported goods and services.     

Intertemporal Equity and Hartwick's Rule in an Exhaustible Resource Model*

In a standard exhaustible resource model, it is known that if, along a competitive path, investment in the augmentable capital good equals the rents on the exhaustible resource (known as Hartwick's rule), then the path is equitable in the sense that the consumption level is constant over time. In this paper, we show the converse of this result: if a competitive path is equitable, then it must satisfy Hartwick's rule.     

Policy reform and productivity change in Chinese agriculture: A distance function approach

Agricultural policy reform has been an important source of change in the Chinese agricultural sector. The reforms led to productivity growth and helped China to pursue its self-sufficiency goal especially in the grain sector. In order to analyze whether observable productivity growth stems from technologically induced components or from the market induced parts, a multi-input–multi-output model is derived by using an econometric distance function framework. A decomposition allows to distinguish allocative effects, scale effects, technological change, and technical efficiency change. Data on farms in Zhejiang from 1986 to 2000 are used to analyze the impact of policy reform.     

Comparative Advantage in Demand: Experimental Evidence of Preferences for Genetically Modified Food in the United States and European Union

The United States (US) exports more than US$6 billion in agricultural commodities to the European Union(EU) each year, but one issue carries the potential to diminish this trade: use of biotechnology in food production. The EU has adopted more stringent policies towards biotechnology than the US. Understanding differences in European and American policies towards genetically modified (GM) foods requires a greater understanding of consumers’ attitudes and preferences. This paper reports results from the first large‐scale, cross‐Atlantic study to analyse consumer demand for genetically modified food in a non‐hypothetical market environment. We strongly reject the frequent if convenient assumption in trade theory that consumer preferences are identical across countries: the median level of compensation demanded by English and French consumers to consume a GM food is found to be more than twice that in any of the US locations. Results have important implications for trade theory, which typically focuses on differences in specialization, comparative advantage and factor endowments across countries, and for on‐going trade disputes at the World Trade Organization.     

Does individualization help productivity of transition agriculture?

There are large differences across transition countries with respect to agricultural‐sector performance and corresponding scope of farm restructuring and shift to individual farming. In this article we analyze the impact of individualization on productivity growth within an augmented neoclassical growth model framework. This approach allows us to circumvent criticisms on the grounds of lack of theoretical and objective criteria for inclusion of explanatory variables. Furthermore, in the empirical analysis using a panel data covering 15 transition countries over the period 1990–2001 and applying a generalized method of moments with instrumental variable estimator we are able to control for the impact of various factors and the potential endogeneity of variables. Our estimation results are robust and support the view that the shift to individual farming, as well as the overall economic reforms, has positively contributed to the productivity growth in agriculture during the first decade of transition.     

Finite sample multivariate structural change tests with application to energy demand models

This paper considers finite sample motivated structural change tests in the multivariate linear regression model with application to energy demand models, in which case commonly used structural change tests remain asymptotic. As in Dufour and Kiviet [1996. Exact tests for structural change in first-order dynamic models. Journal of Econometrics 70, 39–68], we account for intervening nuisance parameters through a two-stage maximized Monte Carlo test procedure. Our contributions can be classified into five categories: (i) we extend tests for which a finite-sample theory has been supplied for Gaussian distributions to the non-Gaussian context; (ii) we show that Bai et al. [1998. Testing and dating common breaks in multi-variate time series. The Review of Economic Studies 65 (3), 395–432] test severely over-rejects and propose exact variants of this test; (iii) we consider predictive break test approaches which generalize tests in Dufour [1980. Dummy variables and predictive tests for structural change. Economics Letters 6, 241–247] and Dufour and Kiviet [1996. Exact tests for structural change in first-order dynamic models. Journal of Econometrics 70, 39–68]; (iv) we propose exact (non-Bonferonni based) extensions of the multivariate outliers test from Wilks [1963. Multivariate statistical outliers. Sankhya Series A 25, 407–426] to models with covariates; (v) we apply these tests to the energy demand system analyzed by Arsenault et al. [1995. A total energy demand model of Québec: forecasting properties. Energy Economics 17 (2), 163–171]. For two out of the six industrial sectors analyzed over the 1962–2000 period, break and further goodness-of-fit and diagnostic tests allow to identify (and correct) specification problems arising from historical regulatory changes or (possibly random) industry-specific effects. The procedures we propose have potential useful applications in statistics, econometrics and finance (e.g. event studies).     

A step beside the maximin path: Can we sustain the economy by following Hartwick's investment rule?

If sustainability is interpreted as the requirement to sustain consumption or utility at an optimal level, a maximin objective appears to be relevant. The sustained economy is characterized by an optimal investment following Hartwick's investment rule. This paper examines how the sustainability of a production-consumption economy with a non-renewable resource is modified in the neighborhood of the maximin path, i.e. when the consumption and the resource price are not optimal. A Sustainable Consumption Indicator is introduced in order to characterize the sustainability of constant consumption paths, defined as deviations from the maximin path. We describe how an over-consumption jeopardizes future sustainability.     

Nonlinearities and heterogeneity in environmental quality: An empirical analysis of deforestation

We use a panel data set of 59 developing countries over the 1972–1994 period to study the deforestation process. Relying on both parametric and semiparametric models, we examine nonlinearities and heterogeneity in the deforestation process. We first study the existence of an Environmental Kuznets Curve (EKC) and then analyze determinants of deforestation. Our data sample provides no evidence of an EKC. We also find that political institution failures may worsen the deforestation process in developing countries.     

The impact of environmental regulation on productivity in German industries

The objective of this paper is to adjust a traditional total factor productivity (TFP) measure for the direct effect of environmental regulation on material and capital input. For this purpose we consider the fact that part of material input and pollution abatement capital have not been used to increase output but to cover the cost of using the environment as a factor of production. Therefore TFP growth rates are lower if part of the material input is allocated to abatement activities instead of producing output. We propose to treat compliance with environmental regulation as an unproductive input linked to the use of productive material input. Our aim is to answer and discuss two questions: How to measure the effect of environmental regulation on TFP, and does the effect matter. We examine data from 1975–1991 for ten pollution intensive German industries.We would like to thank Cornelia Oßwald for valuable research assistance. We are especially grateful to two anonymous referees for many helpful comments.