农户过度放牧行为产生原因分析--来自黑河流域肃南县的农户调查

我国草地资源位居世界第二位,但目前退化非常严重,已经成为牧区生态环境保护和经济发展的主要制约因素。导致草地退化的原因多种多样,自然因素是不可调控因素,并且在近50年内并非是导致草地大面积退化的主要因素,实际上,人为因素才是最为主要的因素,其中过度放牧是最主要因素之一。农户作为草地使用和经营行为的微观主体,其行为可直接或间接地响应所有管理行为和制度的最终效应。通过针对肃南县草地退化进行的农户问卷调查进行详细剖析,并结合有关统计资料,尝试从农户角度阐释过度放牧行为产生的内在机制,认为农户的支出需求增加、收入的增幅减缓与缺乏稳定的收入预期、收入渠道单一以及生态支付意愿不高是导致农户过度放牧行为产生的根本原因。     

Shadow Banking Credit Intermediation： Determinants of Default Risks in Securitization and Collateralization

The growth in shadow banking system over the past few years is acknowledged as the key risk to Malaysia＇s financial stability. This is because that it is associated with growth in the household debts extended by the shadow banks. In line with initiatives by the Bank Negara Malaysia （the Central Bank of Malaysia） to enhance surveillance on the activities of the shadow banks in Malaysia, this study attempts to examine the determinants of default risks of shadow banks restricting to focus on their two main activities： securitization and collateralization. The results provide empirical evidence that future methodology to examine the systemic risks in the shadow banking system may need to account for additional explanatory variables that measure collateralized assets that are being intermediated.     

Do the Retired Elderly in Europe Decumulate Their Wealth? The Importance of Bequest Motives,Precautionary Saving,Public Pensions,and Homeownership

We use microdata on a large number of European countries from the Survey of Health, Ageing and Retirement in Europe (SHARE) to examine the wealth accumulation (saving) behavior of the retired elderly in Europe. We find that less than half of the retired elderly in Europe are decumulating their wealth and that the average wealth accumulation rate of the retired elderly in Europe is positive though relatively moderate (6.6 percent over a 3-year period). These findings suggest that the Wealth Decumulation Puzzle (the tendency of the retired elderly to not decumulate their wealth or to decumulate their wealth more slowly than expected) applies in the case of Europe. Moreover, our regression results suggest that bequest motives, generous public pension systems, and the reluctance of retired elderly homeowners to sell or borrow against their owner-occupied housing are the primary explanations for the existence of the Wealth Decumulation Puzzle in Europe.     

Trade-threshold Effect on Inflation in Tunisia: New Evidence Resulting from a Nonlinear Approach

Trade openness is an important determinant of the inflation process. The effect of trade openness on inflation, however, is still an issue of debate at both theoretical and empirical levels. This study tried to provide a contribution to the literature by examining the relationship between inflation and trade openness in Tunisia over the period 1975Q1-2015Q4 using a nonlinear model. The originality of this study stems from the fact that it is the first investigation considering both the Residual-Based Tests for Cointegration in Models with the Regime Shifts and Threshold Regression model. The linear model confirms the existence of a positive relationship between inflation and trade in Tunisia. Yet, considering the nonlinear model, trade openness growth and Consumer Price Index (CPI) inflation growth show a statistically significant negative link as long as the trade openness evolution does not exceed the threshold. Nevertheless, if the trade openness growth is higher than the threshold, integrating the trade positively affects CPI inflation. Furthermore, a positive influence of Money supply growth on this type of inflation was noticed in Tunisia in all the considered regimes proving the effect of monetary factors on inflation level. Consequently, trade openness could be used to control inflation in Tunisia.     

广义虚拟经济视角下农业领域FDI的技术溢出

以广义虚拟经济视角观察我国农业领域外商直接投资（FDI）活动,可以发现,FDI效应分为物质态表现形式与信息态表现形式。对FDI信息态的有效利用,不仅与东道国的经济发展水平有关,而且与科研人员积极性以及创新能力有关。本文基于我国1999-2011年的省际面板数据,利用负二项回归模型分析我国农业领域外商直接投资（FDI）的技术溢出效应,并利用面板数据的非线性门槛效应模型,分析我国农业领域FDI技术溢出差别的条件,结果表明只有科研人员积极性以及自主创新能力达到一定水平,FDI的信息态才是可吸收的。     

Is there a Laffer curve between aggregate output and public sector employment?

This paper develops a model of the relationship between public sector employment, total output and aggregate real demand in market prices, where public employment has a positive productivity effect on private output. Public employment crowds out private employment and output because its increase induces higher wages and taxes. The valuation of government output is also taken into account. While public employment affects total output and aggregate real demand in an a priori ambiguous way, numerical simulations suggest that the relationship may be nonlinear; positive, when public sector is “small” and negative, when it is “large”. Using the annual data from 22 OECD countries over the period 1960–1996 and estimating and testing for threshold models and more commonly used specifications with multiplicative interaction terms give support to this nonlinearity hypothesis between public employment and private sector output. First version received: October 1996/Final version received: April 2000