CES and Translog parameter estimates in a SAM-based regional general equilibrium framework

The computation of General Equilibrium models crucially depends on Social Accounting Matrix (SAM)-based calibration and on how estimation/imputation are performed to reproduce the benchmark dataset as an equilibrium solution. In this paper, theoretical contributions are provided by suggesting a new procedure in which the production function parameters and the elasticity of substitution are estimated by resorting to the data contained in the SAM. To this aim, the Generalized Cross-Entropy estimator is used. Application of this self-contained procedure to the regional SAM for the Italian region Tuscany leads to empirical results consisting of the estimates of the elasticities of substitution of Constant Elasticity of Substitution and Translog production functions consistent with the theoretical background. This yields a more efficient and effective solution of Computable General Equilibrium models.     

Assessing adaptive capacity of water management organizations. The case study of the municipality of Tomave (Bolivia)

Climate change is only one of several pressure and drivers, such as natural disasters, improvements in technologies and changing customers’ behaviors that water organizations have to relate and adapt to. This places new challenges (e.g. dealing with increased exposure, vulnerability, and uncertainty) to water management and require water organizations to change their perspective on how to deal with water issues. This paper builds on a literature review to identify dimensions and criteria of adaptive capacity and presents a conceptual framework to assess organizational adaptive capacity. The developed framework has been tested within the Municipality of Tomave (Bolivia). The paper results emphasize the incapacity to transform routines as the context is changing leads to the construction of barriers and to the inability of an organization to support the process of change of the society. In addition, the study emphasis that the development of a working system based on cooperation requires first that an organization acquires skills and adapt its routines to the new working system. Furthermore, the development of a participatory process of planning and implementation of policies would help to reduce the trade-offs and conflicts related to water management. Linked to this, the development of a system for monitoring and evaluation of policies implemented organization can contribute to build an iterative mechanism so to allow a redefinition and improvement of such policies.     

Structure and Dynamics of Livestock Marketing in Rural Uganda: Constraints and Prospects for Research and Development

ABSTRACT

The projected global expansion in consumption of meat and other livestock products potentially offers sub-Saharan African small-holder farmers opportunities to escape from the poverty trap. A necessary condition for exploiting this potential is the establishment of marketing systems that provide farmers with reasonable incentives to participate in the market. In this study, the functioning of livestock markets in rural Uganda is analyzed based on a survey of 401 livestock keepers, complimented with focus group discussions with livestock traders and policy planners. The first part is dedicated to the empirical analysis of key organizational and institutional arrangements. Constraints along the marketing chain as well as potential institutional solutions are illuminated. The second part is dedicated to propositions of new areas where more work and new results are needed to improve the functioning of the livestock marketing chain. Empirical findings indicated the following institutional constraints: a poor market information system, lack of grades and standards, lack of trade finance, poor contract enforcement and dispute settlement, disorganized actors, high transaction risks, and poorly developed marketing infrastructure. The study recommends a structured approach to livestock marketing, market infrastructure development, and emphasis on arbitration systems as specific ways of improving the efficiency of livestock marketing in Uganda and other developing countries.     

A socio‐economic assessment of cowpea diversity on the Ghanaian market: implications for breeding

Given the importance of cowpea [Vignaunguiculata(L)Walp] in fighting malnutrition and poverty, a socio‐economic assessment of cowpea diversity found on the Ghanaian market was conducted. The objective was to investigate emerging consumer preference for cowpea and make recommendations for the development of tailor‐made varieties. Forty‐seven cowpea accessions were collected from traders interviewed for morphological characterization to ascertain the degree of diversity. Data was subjected to Hierarchical Cluster Analysis using Genstat Discovery Edition 3 software and variations among the cowpea varieties based on the selected seed traits established. Cowpea varieties found on the markets were broadly categorized into foreign and local varieties and usually named after their sources. Foreign Cowpea varieties were very popular on the markets surveyed as reflected in the per cent distribution of respondents by cowpea varieties sold; Niger (52%), Burkina Faso (50%), Togo (46%), Lagos (36%) and Ghana (18–21%). At the trader level, the order of preference for cowpea characteristics was cleanliness (stone free and no dirt), colour (white seed colour), easy to cook, taste, size, less weevil damage, dryness and place of origin ranked in decreasing order of importance. At the consumer level, cleanliness that was also tied to the extent of weevil damage was ranked most important. This was followed by seed colour (preferable white), short cooking time, size and taste. From the sociological perspective, concerns are raised on the impact of past cowpea breeding activities giving the level of competitiveness and market performance of locally improved varieties observed. Recommendation is made for traders and consumers to be considered as relevant actors in all the stages of crop improvement and breeding activities. This is crucial for enhanced small‐holder farmer market access and strengthened food networks in rural economies.     

Does it Pay to Work for Free? Negative Selection and the Wage Returns to Volunteer Experience

This paper offers the first instrumental variables estimates of the wage returns to volunteer experience. The returns are substantial and differ considerably by gender. The results imply that the unequal valuation of volunteer experience by gender is more important in explaining the gender earnings gap than is the unequal valuation of part‐time paid work experience. The results also indicate negative selection into unpaid work. In a simple model of optimal volunteering, negative selection implies that a lower cost of volunteering would produce both an expanded and higher‐skilled pool of volunteers, and greater societal benefits from volunteer work.     

Stochastic differential equation modeling the prevalence of rare chronic diseases with an application to systemic lupus erythematosus

In this article we describe a system of stochastic differential equations to model the age‐specific prevalence of rare chronic diseases from incidence and mortality rates. As an application, the age profile of the prevalence of systemic lupus erythematosus in England and Wales in1995 is calculated. The results are in good agreement with the observed epidemiological measures.     

JOB SEARCH WITH BIDDER MEMORIES*

This article revisits the no‐recall assumption in job search models with take‐it‐or‐leave‐it offers. Workers who can recall previously encountered potential employers in order to engage them in Bertrand bidding have a distinct advantage over workers without such attachments. Firms account for this difference when hiring a worker. When a worker first meets a firm, the firm offers the worker a sufficient share of the match rents to avoid a bidding war in the future. The pair share the gains to trade. In this case, the Diamond paradox no longer holds.     

Random incentive systems in a dynamic choice experiment

Experiments frequently use a random incentive system (RIS), where only tasks that are randomly selected at the end of the experiment are for real. The most common type pays every subject one out of her multiple tasks (within-subjects randomization). Recently, another type has become popular, where a subset of subjects is randomly selected, and only these subjects receive one real payment (between-subjects randomization). In earlier tests with simple, static tasks, RISs performed well. The present study investigates RISs in a more complex, dynamic choice experiment. We find that between-subjects randomization reduces risk aversion. While within-subjects randomization delivers unbiased measurements of risk aversion, it does not eliminate carry-over effects from previous tasks. Both types generate an increase in subjects’ error rates. These results suggest that caution is warranted when applying RISs to more complex and dynamic tasks.