中国的就业问题及其对策

在未来的十几年,中国将面临严峻的总量性失业和结构性失业问题。总量性失业和结构性失业都会扩大城乡收入差距,不利于社会的安定团结和长期增长。结构性失业阻碍产业结构的升级和城乡二元经济结构的消除,从而不利于我国经济的长期增长。除了人口基数大之外,赶超战略是我国总量性失业和结构性失业的最主要原因。最后,本文提出了长期和短期的政策建议。     

Bayesian belief networks as a meta-modelling tool in integrated river basin management — Pros and cons in evaluating nutrient abatement decisions under uncertainty in a Norwegian river basin

A Bayesian network approach is used to conduct decision analysis of nutrient abatement measures in the Morsa catchment, South Eastern Norway. The paper demonstrates the use of Bayesian networks as a meta-modelling tool in integrated river basin management (IRBM) for structuring and combining the probabilistic information available in existing cost-effectiveness studies, eutrophication models and data, non-market valuation studies and expert opinion. The Bayesian belief network is used to evaluate eutrophication mitigation costs relative to benefits, as part of the economic analysis under the EU Water Framework Directive (WFD). Pros and cons of Bayesian networks as reported in the literature are reviewed in light of the results from our Morsa catchment model. The reported advantages of Bayesian networks in promoting integrated, inter-disciplinary evaluation of uncertainty in IRBM, as well as the apparent advantages for risk communication with stakeholders, are offset in our case by the cost of obtaining reliable probabilistic data and meta-model validation procedures.     

The stability likelihood of an international climate agreement

Results derived from empirical analyses on the stability of climate coalitions are usually very sensitive to the large uncertainties associated with the benefits and costs of climate policies. This paper provides the methodology of Stability Likelihood (SL) that links uncertainties about benefits and costs of climate change to the stability of coalitions. We show that the concept of SL improves upon the robustness and interpretation of stability analyses. Moreover, our numerical application qualifies conclusions from a recent strand of literature based on stylised models with ex-ante symmetric players that learning has a negative impact on the success of coalition formation in context of uncertainty.      

An empirical approach to ecosystem-based fishery management

Marine scientists and policymakers are encouraging ecosystem-based fishery management (EBFM), but there is limited guidance on how to operationalize the concept. We adapt financial portfolio theory as a method for EBFM that accounts for species interdependencies, uncertainty, and sustainability constraints. Illustrating our method with routinely collected data available from the Chesapeake Bay, we demonstrate the gains from taking into account variances and covariances of gross fishing revenues in setting species total allowable catches. We find over the period from 1962-2003 that managers could have increased the revenues from fishing and reduced the variance by employing EBFM frontiers in setting catch levels.     

Natural vs. financial insurance in the management of public-good ecosystems

In the face of uncertainty, ecosystems can provide natural insurance to risk averse users of ecosystem services. We employ a conceptual ecological-economic model in which ecosystem management has a private insurance value and, through ecosystem processes at higher hierarchical levels, generates a positive externality on other ecosystem users. We analyze the allocation of (endogenous) risk and ecosystem quality by risk averse ecosystem managers who have access to financial insurance, and study the implications for individually and socially optimal ecosystem management, and policy design. We show that while an improved access to financial insurance leads to lower ecosystem quality, the effect on the extent of the public-good problem and on welfare is determined by ecosystem properties. We derive conditions on ecosystem functioning under which, if financial insurance becomes more accessible, (i) the extent of optimal regulation increases or decreases; and (ii) welfare, in the absence of environmental regulation, increases or decreases.     

不确定性产生的根源及其降低机制

交易费用和选择成本的存在是不确定性产生的根源.本文通过建立制度-品牌模型,在分析不确定性产生根源的基础上.分析了制度和品牌降低不确定性的作用机制,即制度和品牌分别通过降低交易费用和选择成本使现实经济运行不断逼近新古典经济学的确定性的理想状态.本文的研究旨在丰富与完善经济学中的不确定性理论.     

教育深化、社会资本差异与我国代际收入公平——新"读书无用论"引发的思考

构建社会主义和谐社会需要高度关注代际收入公平问题。通过子代收入决定模型的分析,可以看出高、低收入家庭教育投资时子代的预期薪水在很大程度上影响代际收入公平。教育深化在为不同收入家庭的子代提供更多接受高等教育机会的同时,也导致大学生就业困难、预期薪水下降等知识失业问题。在当前完全竞争的劳动力市场尚未完全建立、就业方式还存在双轨制的条件下,高收入家庭的子代更可能依靠其父代较高的社会资本来谋求一份薪水更高的工作。这无形中扩大了高、低收入家庭子代的收入差距,致使教育在促进代际收入公平方面的功能日趋减小。     

Competition and bargaining in vertical relationships with market uncertainty

We go through the decision to vertically integrate or its opposite, outsource, in an uncertain environment. We consider two different market strategies, price setting and quantity setting and two different vertical relationships: an (imperfectly) competitive one following Stackelberg mode and a more cooperative one with bargaining. In the first scenario, with certainty, price and quantity settings are alike, while with uncertainty the ranking changes. If a bargaining framework is adopted instead, quantity setting under uncertainty leads to an asymmetric distribution of realized gains along the vertical chain. Price setting turns out to be more equitable for firms and preferable even by consumers.

Uncertainty avoidance and the rate of business ownership across 21 OECD countries, 1976–2004

Persistent differences in the level of business ownership across countries have attracted the attention of scientific as well as political debate. Cultural as well as economic influences are assumed to play a role. This paper deals with the influence of cultural attitudes towards uncertainty on the rate of business ownership across 21 OECD countries. First, the concepts of uncertainty and risk are elaborated, as well as their relevance for entrepreneurship. An occupational choice model is introduced to underpin our reasoning at the macro-level. Second, regression analysis using pooled macro data for 1976, 1990 and 2004 and controlling for several economic variables, yields evidence that uncertainty avoidance is positively correlated with the prevalence of business ownership. According to our model, a restrictive climate of large organizations in high uncertainty avoidance countries pushes individuals striving for autonomy towards self-employment. Regressions for these 3 years separately show that in 2004, this positive correlation is no longer found, indicating that a compensating pull of entrepreneurship in countries with low uncertainty avoidance may have gained momentum in recent years. Third, an interaction term between uncertainty avoidance and GDP per capita in the pooled panel regressions shows that the historical negative relationship between GDP per capita and the level of business ownership is substantially weaker for countries with lower uncertainty avoidance. This suggests that rising opportunity costs of self-employment play a less important role in this cultural environment, or are being compensated by increasing entrepreneurial opportunities.

Romer revisited: long-term changes in the cyclical sensitivity of unemployment

In this paper we employ microeconomic evidence on the unemployment experiences of American males to evaluate the sensitivity of unemployment to business cycle fluctuations in the late nineteenth century as compared to the mid-twentieth century. Our results indicate a substantial decline in the value of the Okun coefficient (from −0.65 to −0.32) between the 1890s and the 1960s. These findings challenge Christina Romer’s interpretation that the measured decline in cyclical volatility of unemployment over the twentieth century was created by improvements in the statistical record. Rather, it was changes in the underlying dynamics of the labor market over the cycle, most notably the transition to procyclical productivity patterns and the shift from an added to a discouraged worker effect among secondary workers, which may be summarized as the development of modern labor market behavior, that account for the declining cyclical sensitivity of employment and the drop in the cyclical volatility of unemployment over the century.