An alternative procedure for taking a random sample

Summary The procedure proposed consists in going through the population to be sampled item by item deciding each time with probability p whether the item at hand shall be incorporated in the sample. The "distances" between successive items in the sample will then form a random sample from a geometric distribution. A series of these random distances can easily be produced on a computer and can be conveniently used for taking the sample required. In some cases this method may have its advantages over the conventional use of a table of random numbers.     

Surrogate modelling of a detailed farm-level model using deep learning

Technological change co-determines agri-environmental performance and farm structural transformation. Meaningful impact assessment of related policies can be derived from farm-level models that are rich in technology details and environmental indicators, integrated with agent-based models capturing dynamic farm interaction. However, such integration faces considerable challenges affecting model development, debugging and computational demands in application. Surrogate modelling using deep learning techniques can facilitate such integration for simulations with broad regional coverage. We develop surrogates of the farm model FarmDyn using different architectures of neural networks. Our specifically designed evaluation metrics allow practitioners to assess trade-offs among model fit, inference time and data requirements. All tested neural networks achieve a high fit but differ substantially in inference time. The Multilayer Perceptron shows almost top performance in all criteria but saves strongly on inference time compared to a Bi-directional Long Short Term Memory.     

Agriculture and climate change in global scenarios: why don't the models agree

Agriculture is unique among economic sectors in the nature of impacts from climate change. The production activity that transforms inputs into agricultural outputs involves direct use of weather inputs (temperature, solar radiation available to the plant, and precipitation). Previous studies of the impacts of climate change on agriculture have reported substantial differences in outcomes such as prices, production, and trade arising from differences in model inputs and model specification. This article presents climate change results and underlying determinants from a model comparison exercise with 10 of the leading global economic models that include significant representation of agriculture. By harmonizing key drivers that include climate change effects, differences in model outcomes were reduced. The particular choice of climate change drivers for this comparison activity results in large and negative productivity effects. All models respond with higher prices. Producer behavior differs by model with some emphasizing area response and others yield response. Demand response is least important. The differences reflect both differences in model specification and perspectives on the future. The results from this study highlight the need to more fully compare the deep model parameters, to generate a call for a combination of econometric and validation studies to narrow the degree of uncertainty and variability in these parameters and to move to Monte Carlo type simulations to better map the contours of economic uncertainty.     

Eliciting Willingness‐to‐Pay through Multiple Experimental Procedures: Evidence from Lab‐in‐the‐Field in Rural Ghana

This paper has the objectives of (a) comparing estimated willingness‐to‐pay (WTP) across three elicitation mechanisms (a Becker‐DeGroot‐Marschak [BDM] auction, a kth price auction, and a choice experiment [CE]) and (b) examining how these vary by participation fee. The product under consideration is kenkey made with nutritious maize, biofortified with vitamin A, which gives it a distinct orange color, in contrast to the white and yellow varieties that are traditionally consumed. We use an experiment consisting of 14 treatment arms, conducted in rural Ghana. Our estimation strategy explicitly accounts for the censored (typically at the market price) nature of the bids in the auctions, and the apparently lexicographic choices of several individuals in the CE. We find no evidence of economically meaningful (defined by the minimum currency unit of five pesewas) differences in WTP (although they may be statistically significant) across elicitation mechanisms, or by participation fee, a result that is in contrast to that found in much of the literature. A secondary finding is that the provision of nutrition information positively and significantly affects the marginal WTP for the new maize.     

Gender equality still on the European agenda—but for how long?

While the momentum has certainly not yet disappeared from the gender equality agenda within Europe, the impact of that agenda remains patchy. Progress within individual member states has been significant but not always steady or cumulative. At the European level more attention has been paid to the gender pay gap but policy initiatives remain weak. The loss of the equal opportunities pillar in the new employment guidelines puts this momentum at risk but the new phase still includes commitments to an integrated strategy of gender mainstreaming and equal opportunities.     

The ups and downs of European gender equality policy

In 2003, equal opportunities policy in the European Union suffered both ups and downs. New opportunities came in the guise of the hotly contested new directive on gender equality outside the field of employment, in the invitation to present the first of an annual report on equality between women and men to the Spring Council, in the consolidation of gender mainstreaming within the second round of the National Action Plans on social inclusion and in the new commitments to ‘substantial reductions by 2010’ in gender gaps in employment, unemployment and pay that were included in the new employment guidelines in 2003. These new guidelines presented, however, a major challenge to gender equality as the new phase of the European Employment Strategy dispensed with the four pillars, and therefore the equal opportunities pillar. Instead gender equality became just one of 10 new guidelines. In December the launch of the Employment Taskforce report appeared to push employment policy back more to a ‘full employment with flexibility’ approach and away from concerns with job quality. The focus was therefore more on the integration of women into employment rather than on closing the equality gap.     

Shared Sectoral Growth Versus the Dual Economy Model: Evidence from Côte d'Ivoire,Ghana, and Zimbabwe

Abstract: Though recently challenged, the dual economy view has affected development economics and development policy, either explicitly or implicitly, for more than half a century. According to this view, agriculture merely serves to build the industrial sector — in particular, agriculture has no role as an engine of growth in the long term. Examining agriculture, industry and service sector growth in Côte d'Ivoire, Ghana, and Zimbabwe over more than three decades, we find little empirical support for this view. On the contrary, our analyses find a large degree of interdependence in long‐run sectoral growth, implying that the sectors ‘grow together’ or, similarly, that there are externalities or spillovers between sectors. Policy implications are also discussed; these include directing more attention towards the interdependencies in sectoral growth broadly defined. In particular, our findings have implications for the design of education and health programs, as well. This improved understanding of inter‐sectoral dynamics at all levels may facilitate policy implementation aimed at increasing economic growth — and thereby ultimately improving peoples' livelihoods — in Africa and elsewhere.     

Opening services markets within Europe: Modelling foreign establishments in a CGE framework

Foreign direct investment (FDI) in services is often more important to supply foreign markets than cross-border trade. A complete analysis of services liberalization therefore requires the modelling of FDI. This paper presents the treatment of FDI in our CGE model WorldScan based on the ideas of Petri [Petri, P.A., 1997. Foreign direct investment in a computable general equilibrium framework. Paper Prepared for the Conference, Making APEC work: Economic Challenges and Policy Alternatives, March 13–14. Keio University, Tokyo] and Markusen [Markusen, J.R., 2002. Multinational Firms and The Theory of International Trade. MIT Press] that firms which establish affiliates abroad also transfer firm-specific knowledge. Consequently, capital owned by suppliers from home and foreign countries are not perfect substitutes. We apply this model to the proposals of the European Commission to open up services markets. Even when FDI in services could increase by 20% to 35%, the overall economic impact is limited. Our assessment suggests that GDP in the EU25 could increase up to 0.4%. These effects could be up to 0.8% higher if foreign capital also increases the overall productivity of the services sector.