MODELING SOVEREIGN RISKS: FROM A HYBRID MODEL TO THE GENERALIZED DENSITY APPROACH

Motivated by the European sovereign debt crisis, we propose a hybrid sovereign default model that combines an accessible part taking into account the evolution of the sovereign solvency and the impact of critical political events, and a totally inaccessible part for the idiosyncratic credit risk. We obtain closed‐form formulas for the probability that the default occurs at critical political dates in a Markovian setting. Moreover, we introduce a generalized density framework for the hybrid default time and deduce the compensator process of default. Finally, we apply the hybrid model and the generalized density to the valuation of sovereign bonds and explain the significant jumps in long‐term government bond yields during the sovereign crisis.     

Volatility forecasting: long memory,regime switching and heteroscedasticity

In this article, we account for the first time for long memory, regime switching and the conditional time-varying volatility of volatility (heteroscedasticity) to model and forecast market volatility using the heterogeneous autoregressive model of realized volatility (HAR-RV) and its extensions. We present several interesting and notable findings. First, existing models exhibit significant nonlinearity and clustering, which provide empirical evidence on the benefit of introducing regime switching and heteroscedasticity. Second, out-of-sample results indicate that combining regime switching and heteroscedasticity can substantially improve predictive power from a statistical viewpoint. More specifically, our proposed models generally exhibit higher forecasting accuracy. Third, these results are widely consistent across a variety of robustness tests such as different forecasting windows, forecasting models, realized measures, and stock markets. Consequently, this study sheds new light on forecasting future volatility.     

The saving–investment correlation puzzle is still a puzzle

A number of simulation studies claim to have solved the Feldstein–Horioka puzzle by demonstrating that a high time-series correlation between saving and investment naturally arises from business cycle shocks. This paper uses panel data of saving and investment controlled for business cycle shocks to empirically test the significance of cyclical shocks — productivity, fiscal and the terms of trade shocks — in explaining a high saving–investment correlation. The estimation results reveal that conventional aggregate shocks only partially explain the high saving–investment correlation. Moreover, country differences in the size of the GNP and the non-traded sector do not significantly affect the saving–investment correlation. The saving–investment correlation puzzle remains a puzzle after all.     

中国"以电子政务拉动信息产业发展"政策的再评估

电子政务是中国信息化战略的重中之重，但其实际发展与预期间存在着明显差距。本文以中国“以电子政务拉动信息产业发展”政策为研究重点，把这一政策放在中国信息化历史中加以考察，分析中国信息化新阶段ICT市场的新变化和新挑战，针对电子政务实践与预期间的差距，对该政策提出我们的看法。     

新形势下我国耕地保护的长效机制研究

耕地是人类赖以生存的物质基础，是国民经济和社会发展的宝贵资源，耕地数量的多少和质量优劣直接关系到国家粮食安全和社会稳定。因此，在新形势下，如何保护好有限的耕地资源，促进经济社会科学、合理地发展，已成为当今世界的重大课题。本文根据我国耕地减少的现实危机及原因，提出一套科学、合理的耕地保护长效机制，力求为进一步有效地保护耕地资源提供理论基础和现实途径。     

Tinbergen in De Economist

Jan Tinbergen's scientific writings cover six main areas of research. His articles in De Economist represent these areas; in some cases the contributions to De Economist were of a pioneering nature (business cycles, economic models, economic integration); in others De Economist was the first or even single outlet for Tinbergen's work. This article provides an overview of these contributions. The wide scope of Tinbergen's areas of research goes together with a unity in approach, the characteristics of which are: policy relevance, quantification and measurement, balance in analysis and presentation, and learning from experience. Tinbergen's articles in De Economist bear witness to this approach which at the time also met with scepticism and resistance as this overview shows. According to Houthakker, Tinbergen's main contribution may be that, amidst the pleas of interest groups and the slogans of the laity, an attempt is made that the voice of the professional economic researcher be heard. Tinbergen's work still sets an agenda for both economic research and policy making.     

What do interest rates reveal about the functioning of real business cycle models?

This paper begins by documenting the extent to which the predictions of standard Real Business Cycle (RBC) models are incompatible with observed movements in real interest rates. The main finding of the paper is that extending the baseline model to include habit persistence in consumption and adjustment costs to capital significantly improves the model's empirical performance. In our evaluation of the model's performance, we take special care of estimating and testing predictions of the model using both moments drawn directly from the data and moments calculated after identifying shocks to the stochastic trend.     

企业长期激励机制创新

长期激励机制匮乏问题一直是我国理论界和实业界最为关注的核心问题。指出目前在我国实行的长期激励措施的不足,提出了以“股息期权”,代替“股票期权”的激励方案,从而有效解决了我国目前的资本市场和法律法规对于“长期激励形式”的约束,可以为现阶段企业管理者进行薪酬激励机制设计时提供重要的参考和借鉴。     

A monetary business cycle model with unemployment

To reproduce key features of the post-war U.S. data, most monetary business cycle models must assume there are high price markups and that agents have high labour supply elasticities despite the existence of contradictory microeconomic evidence. This paper eliminates the need for these assumptions by introducing imperfectly observed effort into a limited participation model. The estimated model is better able to capture the sluggish price response to a monetary policy shock than the standard model, and is consistent with evidence regarding the qualitative responses of the U.S. economy to technology shocks, fiscal policy shocks and monetary policy shocks.     

建立城市环境卫生长效管理机制

当前各地在改善城市环境卫生中常常不能持久稳定。作者根据实践经验 ,提出建立城市环境卫生长效管理运行机制 :由行政推动转向依法管理 ;由多头管理转向专业管理 ;由政府统包向市场运作转变。