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101.
The meaning and identification of poverty are examined usingthree indicators of standard of living in the North Indian villageof Palanpur. The first is intended as a measure of "apparentprosperity" based on the personal assessments of investigatorsafter intensive field work in the village over the full agriculturalyear 1983–84. The other two are income in 1983–84,and a measure of permanent income obtained by averaging incomesfrom four surveys conducted over a twenty-six-year interval.A comparison of these three indicators shows that income measuredin any one year may give a misleading impression of the incidenceof poverty. The risk of poverty for households is calculated.Vulnerability is high among low-caste households and those whichare involved in agricultural labor. Categories, however, arenot homogeneous; for example, whereas the landless and widowsare more likely to be poor, some of such households are quitewell off. It is argued that poverty in a good agricultural yearis a better indicator of sustained poverty than poverty in abad year. Occupational mobility out of agricultural labor islow, and changes in the distribution of land are largely accountedfor by demographic processes such as household splits.  相似文献   
102.
Many large lake ecosystems are experiencing increasing eutrophication and persistent cyanobacteria‐dominated algal blooms affecting their water quality and ecosystem productivity because of widespread non‐point and point nutrient sources. Accordingly, the present study utilized data of July 2003 and January–February 2004, as well as previous measurements of nutrients and physico‐chemical variables (electrical conductivity, dissolved oxygen, temperature, pH, turbidity and chlorophyll‐a), to characterize the spatial and temporal trends, as a means of better understanding the factors influencing lake environmental conditions, as support tools for long‐term ecosystem management and for better understanding the long‐term trends and effects. Inshore gulf areas were found to represent zones of maximum nutrient concentrations, compared to the deep main lake zones, with significant inter‐parameter correlations. Phosphorus, silicon and chlorophyll‐a concentrations were significantly correlated. Water electrical conductivity was also significantly and positively correlated with soluble reactive silicon (SRSi), alkalinity hardness DO, while exhibiting a negative association with water transparency. Water turbidity and transparency, electrical conductivity, and SRSi concentrations clearly describe a gradient from the gulf into the main lake. For such a shallow gulf, these findings suggest primary productivity is influenced mainly by the availability of nutrients, light transparency and the extent of availability of resuspended nutrients. The increasing eutrophic state of Lake Victoria is a serious concern since it contributes to an increased potential of more frequent occurrences of cyanobacterial blooms, a potential public health risk to both humans and wildlife. Improved understanding of influences from previous fish species introductions and concomitant changes in indigenous fish species, increased lake basin population and anthropogenic activities, water hyacinth resurgences, sustainability of biodiversity, and current interests in cage farming, are among the major concerns and challenges facing the contemporary Lake Victoria. The trends regarding nutrients and physico‐chemical characteristics are intended to support better monitoring efforts and data to promote the lake's ecosystem services and the sustainable management of the lake ecosystem.  相似文献   
103.
The floodplain wetlands of the southern Murray Darling Basin (MDB) have been subject to the impacts of catchment and water resource development for more than a century. Their current degraded state is attributed to the regulation of the rivers and abstraction of water volume for irrigation. The MDB Plan is to return at least 2,750 Gl of mean annual flow to the system to restore the condition of waterways. Considerable recent investment in infrastructure enables water to be released into the basin's floodplain wetlands. The proposed watering regime is underpinned by modelling that suggests that, before regulation, overbank flows would have occurred regularly as discharge peaked in winter and spring. Sediment cores have been extracted from over 50 floodplain wetlands of the southern Murray Basin. Those from several, large meander wavelength billabongs extend for 1,000–5,000 years suggesting that these sites were permanently inundated over that time. Others extend to ~200 years and are presumed not to have accumulated sediment until more recently. The records of most wetlands, however, only extend to the onset of river regulation in the 1920s, suggesting that before then they were not inundated for sufficient duration for net accumulation to occur. Preserved diatoms suggest that the shallow, plant‐dominated wetlands of the past have transitioned to deep, turbid water systems today. As rivers are identified as a source of sediment to wetlands, less regular inundation, rather than more, is a viable option in restoring the ecological function of these floodplain wetlands and in slowing sediment infill.  相似文献   
104.
ABSTRACT ** :  We investigate a bureaucratic principal responsible for the procurement of goods and services from private agents. The bureaucrat is evaluated on output and controlled by a limited budget. The agents maximize profit, have private information about variable production costs, and have positive outside options which are lost upon acceptance of a procurement contract. The setting is relevant for, e.g. governmental agencies. We show how this setup makes probabilistic rationing and overproduction for low-cost agents a useful tool for the bureaucrat.  相似文献   
105.
With the collapse of communism in the late 1980s the field of comparative political economy has undergone major revision. Socialism is no longer considered the viable alternative to capitalism it once was. We now recognize that the choice is between alternative institutional arrangements of capitalism. Progress in the field of comparative political economy is achieved by examining how different legal, political and social institutions shape economic behavior and impact economic performance. In this paper we survey the new learning in comparative political economy and suggest how this learning should redirect our attention in economic development.JEL classification: B53, O10, O20, P0  相似文献   
106.
Interdependent preferences generally imply Pareto inefficiency. For a general demand system, we provide a characterization of Pareto improvements. For a prominent parametric specification, the Linear Expenditure System, we characterize in detail the welfare loss associated with interdependent preferences. Using an estimated empirical model of this kind, we calculate the compensating variation corresponding to the welfare loss.  相似文献   
107.
Legislative Bargaining and Coalition Formation   总被引:1,自引:0,他引:1  
The finite horizon version of D. P. Baron and J. Ferejohn's [1989, Amer. Polit. Sci. Rev.83, 1181-1206] legislative bargaining model is investigated. With three or more periods, a continuum of divisions is supportable as subgame perfect equilib- ria. There exist equilibria where coalitions larger than a minimal winning coalition receive strictly positive shares. With sufficiently patient players and a sufficiently long horizon, any interior distribution is supportable as an equilibrium. In contrast, a generic uniqueness result applies when introducing heterogenous time preferences. The unique backwards induction equilibrium in the perturbed game is nonstationary, and neither the original (symmetric) nor the perturbed game provides guidance for equilibrium selection in the infinite game. Journal of Economic Literature Classification Numbers: C73, C78, D72, D78, H49.  相似文献   
108.
Summary. This paper reexamines the condition (1 + n), which Zilcha (1991) presents as a necessary and sufficient condition for dynamic inefficiency of stationary allocations in overlapping generation models with stochastic production. We show that this condition is necessary but not sufficient for a stationary allocation to be dynamically inefficient by Zilchas definition. We also show that there is a narrow but widely studied class of specifications in which the Zilcha test is both necessary and sufficient for dynamic inefficiency of stationary competitive equilibrium allocations. Outside this class, however, counterexamples can be constructed relatively easily.Received: 30 September 2002, Revised: 13 August 2004, JEL Classification Numbers: D51, D90, E13, E22. Correspondence to: Steven RussellWe thank Jon Burke, Subir Chakrabarti, Itzhak Zilcha and an anonymous referee for helpful conversations and/or comments.  相似文献   
109.
We argue that the proper specification of a panel gravity model should include main (exporter, importer, and time) as well as time invariant exporter-by-importer (bilateral) interaction effects. In a panel of 11 APEC countries, the latter are highly significant and account for the largest part of variation. First version received: February 2001/Final version received: June 2002 RID="*" ID="*"  We are grateful to two anonymous referees and Robert Kunst for their helpful comments.  相似文献   
110.
Environmental technology foresight: New horizons for technology management   总被引:1,自引:0,他引:1  
Decision-making in corporate technology management and government technology policy is increasingly influenced by the environmental impact of technologies. Technology foresight (TF) and environmental impact assessment (EIA) are analyzed with regard to the roles they can play in developing long-term strategies and policies for reducing the environmental impact of technologies. The methods for TF and EIA are quite well developed, but remain within a tradition of rational decision-making. However, recent studies of tecnology management and innovation have shown that technology development can be explained only to a certain degree by rational decision-making. EIA is usually presented as an objective and scientific method, based on normative underpinnings that usually remain hidden. Thus, systematic information-providing instruments such as TF and EIA can play only a limited role. We propose a procedure for environmental technology foresight. The case is made that environmental technology management will be most helped by a 'constructive' approach in order to stimulate incorporation of long-term environmental objectives.  相似文献   
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