Extension services,product quality and yields: the case of grapes in Argentina

This article studies the impact of publicly subsidized agricultural extension services on yields and product quality. We use panel data from grape producers in Mendoza, Argentina to estimate the impacts of farmer trainings. We find a negative overall impact on yields and evidence of a positive average impact on the adoption of higher‐quality grape varieties. By analyzing the dynamic pattern of the estimated effects, we find evidence of a temporary decrease in yields suggesting the existence of an adjustment process following the introduction of higher‐quality grapes. The overall negative effect on yield is driven by a sharp drop in the year of participation. This fades after year one, and two to three years after treatment we observe increases in higher‐quality grape production. Findings reinforce the importance of temporal dimension of extension services.     

宝丽来之战略标准化管理模型:10项行动原则

摄影业回望 摄影业(photographic indus-try)已经被重新定义为"影像"业("imaging"industry),其组成也不再仅限于照相机、卤化银感光材料.在今天的美国,影像业已经发展成为了包含许多门类、税收高达1550亿美元的重要产业.除了业余和专业的摄影外,影像业还包括复印产品(copying products)和服务、形象艺术(graphic arts)、桌面出版系统(desktop publish-ing)、计算机辅助图像设计、医学诊断、显微镜方法、印刷以及消费者视频(consumer video)等等.     

Valuing nature: From environmental impacts to natural capital

Economic valuation of natural and environmental assets is now a well established practice. Economic analysis provides several methods for discovering the impact on social welfare associated with changes in the ability of these assets to provide different goods and services. In general terms, these valuation exercises have been performed in the framework of Environmental Impact Assessment or, more generally, Cost Benefit Analysis. There is, however, an increasing demand nowadays to go beyond this framework and to value natural capital (natural resource stocks, land and ecosystems) as such. There are two main reasons for this new demand. On the one hand, sustainability requires that proper account should be taken of capital depreciation and, therefore, there is a need to value natural capital changes. This valuation process, nevertheless, only makes sense when some kind of substitution between natural and other forms of capital is allowed. On the other hand, there is also an increasing tendency to demand that the stock of natural capital present in a given territory be valued, either to discover one of the main components of social wealth or to help adequately plan changes in land use. Yet, whereas conventional valuation methods are probably adequate to fulfill the first task, this is less true in the case of the second, while even more difficulties arise in connection with the third one. Even if at first sight the process appears conceptually identical, these tasks are of a different order of magnitude, as the experience of both the World Bank and the Statistics Division of the United Nations in this respect clearly shows.     

Dollarization persistence and individual heterogeneity

A salient feature of financial dollarization, arguably the one that causes most concern to policymakers, is its persistence: even after successful macroeconomic stabilizations, dollarization ratios often remain high. In this paper we argue that this persistence is connected to the fact that the participants in the dollar deposit market are fairly heterogenous, and so is the way they form their optimal currency portfolio. We develop a simple model when agents differ in their ability to process information, which turns out to be enough to generate persistence upon aggregation. We provide empirical evidence that is consistent with this claim.     

Microfinance at a Crossroads

In this essay, we summarize the main features of Yunus' economic thought and discuss whether it is possible to conclude, as seems straightforward according to Yunus (1997) , that microfinance is good for the poor and that it exemplifies a typical activity of social enterprise. To do this, we review some of the contents of the 2006 World Bank/Brookings Institution conference on microfinance as summarized by Barr et al. (2007) .     

Structural VAR Estimation with Exogeneity Restrictions

ABSTRACT Exogenous variables arise quite naturally in macroeconomic models of small open economies. In these models overidentification is also a common feature. In the presence of exogeneity restrictions and overidentification the usual two-steps approach to the estimation of structural VAR's is not equivalent to Maximum Likelihood (ML). We propose a simple modification of that usual approach which produces ML estimators.     

CO-INTEGRATION ANALYSIS AND THE DETERMINANTS OF LAND PRICES

This paper outlines the concept of co-integration and its use in econometric modelling. The techniques of co-integration analysis are described, with particular emphasis given to test procedures. Co-integration between two or more variables is taken to imply the existence of a long-run equilibrium relationship between them. Co-integration analysis is applied in a re-examination of recent empirical models of the determination of land prices in England and Wales. The results suggest that recent land price models do not describe longrun relationships between land prices and the explanatory variables selected. Criticisms of the different measurements of returns to land used in studies to date are sustained by the analysis, and a clear role for interest rates in the determination of land prices is indicated.     

Valuation structure in first-price and least-revenue auctions: an experimental investigation

In many auctions the valuation structure involves both private and common value elements. Existing experimental evidence (e.g. Goeree and Offerman in Am. Econ. Rev. 92(3):625–643, 2002) demonstrates that first-price auctions with this valuation structure tend to be inefficient, and inexperienced subjects tend to bid above the break-even bidding threshold. In this paper, we compare first-price auctions with an alternative auction mechanism: the least-revenue auction. This auction mechanism shifts the risk regarding the common value of the good to the auctioneer. Such a shift is desirable when ex post negative payoffs for the winning bidder results in unfulfilled contracts, as is often the case in infrastructure concessions contracts. We directly compare these two auction formats within two valuation structures: (1) pure common value and (2) common value with a private cost. We find that, relative to first-price auctions, bidding above the break-even bidding threshold is significantly less prevalent in least-revenue auctions regardless of valuation structure. As a result, revenue in first-price auctions is higher than in least-revenue auctions, contrary to theory. Further, when there are private and common value components, least-revenue auctions are significantly more efficient than first-price auctions.