Climate change, irrigation, and Israeli agriculture: Will warming be harmful?

This paper utilizes a Ricardian model to test the relationship between annual net revenues and climate across Israeli farms. The study finds that it is important to include the amount of irrigation water available to each farm in order to measure the response of farms to climate. With irrigation water omitted, the model predicts climate change is strictly beneficial. However, with water included, the model predicts that only modest climate changes are beneficial while drastic climate change in the long run will be harmful. Using the AOGCM Scenarios we show that farm net revenue is expected to increase. Although Israel has a relatively warm climate a mild increase in temperature is beneficial due to the ability to supply international markets with farm product early in the season.     

Domestic Support and Border Measures for Processed Horticultural Products

In horticultural markets, trade barriers often apply to the processed products whereas domestic support applies to farm-produced raw commodities. Here we assess the effects of such trade barriers and domestic support by simulating the effects of policy reform on global processing tomato markets, which are faced with modest processed product tariffs and high domestic support in the European Union (EU). Both protection and EU subsidy drive down world welfare, but we find that reducing import tariffs for tomato products would yield greater effects on markets and larger welfare impacts outside Europe than would reductions in EU domestic support.     

Research on principal-agency of stockholders and managers under asymmetric information condition

In modem enterprises, a separation of the right of ownership and management results in asymmetric information problems between stockholders and managers. In conditions of principal-agency relationship, the game behaviors between principle and agency within enterprises are impacted by asymmetric information. This study discusses the game behaviors between stockholders and managers by using information economic theories from the perspective of asymmetric information. Based on the model of the principal-agency relationship between stockholders and managers, our research uses quantitative analysis to reveal how to achieve maximum profit expected of stockholders through an incomplete contract, under asymmetric information condition.     

蒙代尔-弗莱明模型在发展中大国的适用与延伸

M-F模型是开放经济宏观经济学的基本模型,其存在的缺陷和局限是理论拓展的主要方向。本文对M-F模型的前提假定和分析过程作出了放松和修正,使其适用于发展中大国的情形。并在M-F模型的货币政策效应分析基础上,提出M-F模型在发展中大国的延伸分析方法,即Semi-M-F模型分析方法,指出发展中大国的货币政策是部分起作用的。最后,对Semi-M-F模型分析方法在中国的应用进行评述。     

基于引力模型的中美农产品贸易边境效应研究

针对中美两国在农产品贸易上的新变化,应用引力模型的派生模型——边境效应引力模型对中美两国农产品贸易的流量和流向进行理论和实证研究。首先介绍了边境效应引力模型基本模型的推导过程,并引入了调整模型。然后采用1987至2005年其中5年的截面数据进行计算,结果发现:中美农产品贸易的边境效应显著存在,且呈逐年下降趋势;两国之间的农产品贸易边境效应存在流向和区域上的差异;距离的平方并不影响模型的可靠性。     

Biophysical Model of Larval Yellow Perch Advection and Settlement in Lake Michigan

Potential for large-scale physical transport processes to affect recruitment of Lake Michigan yellow perch (Perca flavescens) was studied by examining the variation in larval distribution, growth rate, and settlement during June–August 1998–2003 using a 3D particle transport model linked with an individual-based bioenergetics growth model. In all years, virtual larvae were released nearshore in southwestern Lake Michigan, a known and important spawning region for yellow perch. For any given year, the same circulation pattern and water temperature either promoted or reduced yellow perch settlement depending on the consumption rates and settlement size chosen in the growth model. Increased consumption increased the number of settled larvae and expanded the total area where larvae settled, whereas increased settlement size reduced the number of settled larvae and reduced the overall settlement area. Interannual variability in circulation patterns and water temperature also resulted in contrasting larval settlement rates, settlement locations, and size of settlement areas between years. Model predictions were most consistent with field observations of age-0 yellow perch from Illinois and Michigan waters when settlement was assumed to occur at 50 mm. Moreover, our model suggests that larvae originating from southwestern Lake Michigan can recruit anywhere within the southern basin and even in the northern basin. Future model improvement will require information on the relative contribution of various sectors to the larval pool, their distribution with reference to the hydrodynamic landscape, the feeding and growth of yellow perch during their pelagic phase, and the size at transition to demersal stage.     

农村劳动力转移模型:基于中国制度背景的构造

本文在对经典的农村劳动力流动模型进行理论梳理的基础上,引入中国的制度变量,试图构建适合中国制度背景的农村劳动力转移模型,同时,运用经验事实对其作进一步的实证检验,并分析了模型的政策含义。     

窄岭金矿剪切带基本特征与发展演化模式

河北丰宁窄岭金矿,可以区分3幕Ⅰ级韧性剪切带,1幕Ⅱ级脆韧性剪切带和1幕Ⅲ级脆性剪切带。伴随不同的剪切变形变质作用,分别有花岗岩(红旗菅子群花岗片麻岩)→闪长岩(变闪长岩)→正长斑岩→含金石英脉的侵位。而金矿则是这种多期多阶段构造—岩浆复杂演化使金逐步富集的最终产物。     

我国城镇居民小康水平评价研究

通过对我国城镇居民小康水平的指标进行分析 ,设置了度量小康水平的评价指标体系 ,构建了评价我国城镇居民小康水平的因子分析模型 ,并应用该模型对我国城镇居民小康水平进行了合理的评价。     

工程建设地质环境质量损益经济评价理论与方法

本文从系统的观点出发,在综合分析了＂地质环境－社会经济＂这一复合大系统运行过程的基础上,提出了工程建设地质环境质量损益经济评价的系统性、综合性、协调性和实用性原则;分析了系统理论、信息理论及控制理论在评价中的运用;并重点就分析指标计算方法体系及综合评价模型进行了研究。