佩皮尼昂:欧洲城市的未来

佩皮尼昂市以其城市规划，以其过去和未来在社会经济文化方面的巨大发展变化，正无可争辩地列入欧洲都市的网络之中。她的地位也从“大的小城市”变为“小的大城市”。     

Optimal dividend policy and growth option

We analyse the interaction between the dividend policy and the decision on investment in a growth opportunity of a liquidity constrained firm. This leads us to study a mixed singular control/optimal stopping problem for a diffusion that we solve quasi-explicitly by establishing a connection with an optimal stopping problem. We characterize situations where it is optimal to postpone the distribution of dividends in order to invest at a subsequent date in the growth opportunity. We show that uncertainty and liquidity shocks have an ambiguous effect on the investment decision.      

Trade unions vs. statistical discrimination: Theory and application to post-apartheid South Africa

A simple model of statistical discrimination is analyzed, which captures some stylized facts of the South African labor market. It shows that this type of discrimination disappears when the wage rates are determined by efficient bargaining between a representative firm and a union, with endogenous membership. This may explain why the wage gap between Black and White workers in post-apartheid South Africa is smaller among unionized workers than among non-unionized ones.     

Crop genetic diversity, farm productivity and the management of environmental risk in rainfed agriculture

This paper presents an assessment of the linkages between cropgenetic diversity, farm productivity and risk management. Aflexible moment-based approach is used to analyse the impactof crop genetic diversity on the mean, variance and skewnessof yield. Using farm-level data from Sicily (Italy), econometricevidence shows how crop genetic diversity can increase farmproductivity and reduce risk exposure. The empirical resultsindicate that crop genetic diversity can reduce variance, butonly if pesticide use is low. Furthermore, high diversity levelscan reduce downside risk exposure (e.g. the risk of crop failure).This provides useful insights on the linkages between resilienceand crop genetic diversity.     

Assessing the Impact of District Primary Education Program in India

We examine the impact of India's District Primary Education Program (DPEP) introduced in the mid‐1990s. We exploit the fact that the DPEP was targeted towards primary school age children and was introduced in phases to different districts in India, and many of the districts never got the program to implement a difference‐in‐difference strategy to find the causal impact of the program on probability of attended primary school, probability of completed primary education and years of schooling. We find that the DPEP program increased the probability of attended primary school and completed primary school by about 2 percentage points. Similarly, the program increased the years of schooling by 0.16 years.     

Price Dynamics in a Vertical Sector: The Case of Butter

We develop a reduced-form model of price transmission in a vertical sector, allowing for refined asymmetric, contemporaneous and lagged, own and cross-price effects under time-varying volatility. The model is used to investigate the wholesale-retail price dynamics in the U.S. butter market. The analysis documents the nature of nonlinear price dynamics in a vertical sector. It finds strong evidence of asymmetric retail price responses, both in the short term and the longer term, but only weak evidence of asymmetric wholesale price responses. Asymmetric retail responses play a major role in generating a skewed distribution of butter prices. The empirical results indicate the presence of imperfect competition at the retail level.     

On Crop Biodiversity, Risk Exposure, and Food Security in the Highlands of Ethiopia

This paper investigates the effects of crop genetic diversity on farm productivity and production risk in the highlands of Ethiopia. Using a moment-based approach, the analysis uses a stochastic production function capturing mean, variance, and skewness effects. Welfare implications of diversity are evaluated using a certainty equivalent, measured as expected income minus a risk premium (reflecting the cost of risk). We find that the effect of diversity on skewness dominates its effect on variance, meaning that diversity reduces the cost of risk. The analysis also shows that the beneficial effects of diversity become of greater value in degraded land.     

On the Use of Price Ratio in Aggregate Supply Response: Some Evidence from the Poultry Industry

The specification of supply/demand relationships has received considerable attention in agricultural economics (Heien 1977). Economic theory has helped provide a basis for the specification of such relationships, one of its contributions being the proposition that prices should be interpreted only in relative terms. This has had a profound influence on model building in agricultural economics, leading a number of researchers to avoid the use of absolute prices in economic analysis. For this reason, numerous market models of the agricultural economy use price ratios as explanatory variables (e.g., Chen; Chen et al.; Heien, 1976; Gerra; Kulshreshtha and Wilson; Rahn; Talpaz; Morzuck et al.; Houck and Gallagher; Wilson et al.); these examples suggest that the use of such ratios is fairly widespread in econometric modeling of the crop and livestock sectors. One of the best examples of price ratios is the "feed cost to price" ratio commonly used in the analysis of livestock supply response. Indeed, since feed cost constitutes a major part of the total production cost in livestock activities, the "feed cost to price" ratio is often considered a proxy for profitability. For this reason, data on such ratios are regularly published for various livestock activities (e.g., USD A). Also, "feed cost to price" ratios are often employed in the specification of models of livestock supply response, (e.g., Chen; Chen et al.; Heien 1976; Gerra; Kulshreshtha and Wilson; Rahn; Talpaz). However, not all models of aggregate supply response follow this approach. For example, Freebairn and Rausser, and Arzac and Wilkinson, use prices as separate variables rather than in ratio forms in their models. In particular, they do not employ price ratios in their livestock and crop supply equations. The existence of these different approaches raises questions about the appropriateness of the use of price ratios in the modeling of aggregate supply.     

The microeconomics of food security

This article develops a dynamic microeconomic model of food security under uncertainty, with special focus on the relationships between food demand, nutrition and human survival. It investigates the influence of entitlements on malnutrition, hunger and starvation under uncertainty. It develops useful insights on the links between food security and a number of policy instruments commonly used in dealing with malnutrition and starvation.     

The state of theory in three premier advertising journals: a research note

Despite its importance, little is known about the prevalence of theory in the literature on advertising research. Utilising a content analysis of the three premier advertising journals over an 11-year period, it is found that only 17% of articles have made explicit use of theory. Psychology is the discipline from which the greatest number of articles drew their theoretical frameworks, followed by sociology and economics – indeed, theories from marketing and advertising are in the minority. Limitations are noted and implications of the results are discussed.