政府采购法的功能

政府采购法是国家调整政府采购过程中产生的各种社会关系的法律规范之总称。在现代经济社会中，政府采购法发挥的作用愈发重要。从行政管理、产业导向和保护市场竞争3个方面出发，对政府采购法的主要功能进行了分析。     

Option hedging theory under transaction costs

The problem of option hedging in the presence of proportional transaction costs can be formulated as a singular stochastic control problem. Hodges and Neuberger [1989. Optimal replication of contingent claims under transactions costs. Review of Futures Markets 8, 222–239] introduced an approach that is based on maximization of the expected utility of terminal wealth. We develop a new algorithm to solve the corresponding singular stochastic control problem and introduce a new approach to option hedging which is closer in spirit to the pathwise replication of Black and Scholes [1973. The pricing of options and corporate liabilities. Journal of Political Economy 81, 637–654]. This new approach is based on minimization of a Black–Scholes-type measure of pathwise risk, defined in terms of a market delta, subject to an upper bound on the hedging cost. We provide an efficient backward induction algorithm for the problem of cost-constrained risk minimization, whose associated singular stochastic control problem is shown to be equivalent to an optimal stopping problem. This algorithm is then modified to solve the singular stochastic control problem associated with utility maximization, which cannot be reduced to an optimal stopping problem. We propose to choose an optimal parameter (risk-aversion coefficient or Lagrange multiplier) in either approach by minimizing the mean squared hedging error and demonstrate that with this “best” choice of the parameter, both approaches have similar performance. We also discuss the different notions of risk in both approaches and propose a volatility adjustment for the risk-minimization approach, which is analogous to that introduced by Zakamouline [2006. European option pricing and hedging with both fixed and proportional transaction costs. Journal of Economic Dynamics and Control 30, 1–25] for the utility maximization approach, thereby providing a unified treatment of both approaches.     

Why Sunk Costs Matter for Bargaining Outcomes: An Evolutionary Approach

Two bargaining parties play the Nash Demand Game to share a pie whose size is determined by one party's investment decision. Various investment levels are subgame-perfect. Adding the investment decision to Young's evolutionary bargaining model yields the following long-run outcome: efficient investment prevails and the investor's share of the pie approximates die maximum of (i) the smallest share that induces efficient investment, even if the investor expects to appropriate the available pie from every inefficient investment, and (ii) half of the pie. The result favors forward induction to subgame consistency and equity theory to hold-ups. Journal of Economic Literature Classification Numbers: C78, L14.     

Forward induction and entry deterrence: an experiment

The Dixit (Econ J 90:95–106, 1980) hypothesis that incumbents use investment in capacity to deter potential entrants has found little empirical support. Bagwell and Ramey (J Econ 27:660–680, 1996) propose a model where, in the unique game-theoretic prediction based on forward induction or iterated elimination of weakly-dominated strategies, the incumbent does not have the strategic advantage. We conduct an experiment with games inspired by these models. In the Dixit-style game, the incumbent monopolizes the market most of the time even without the investment in capacity. In our Bagwell-and-Ramey-style game, the incumbent also tends to keep the market, in contrast to the predictions of an entrant advantage. Nevertheless, we find strong evidence that forward induction affects the behavior of most participants. The results of our games suggest that players perceive that the first mover has an advantage without having to pre-commit capacity. In our Bagwell–Ramey game, evolution and learning do not drive out this perception. We back these claims with data analysis and a theoretical framework for dynamics. Financial support by the Spanish Ministerio de Ciencia and Tecnología (SEC2002-01352 and SEJ2006-11665-C02-01) and the Barcelona Economic Program of CREA and excellent research assistance by David Rodríguez are gratefully acknowledged. The authors thank Aurora García Gallego and Armin Schmutzler for helpful comments.     

Evolutionary dynamics and backward induction

The backward induction (or subgame-perfect) equilibrium of a perfect information game is shown to be the unique evolutionarily stable outcome for dynamic models consisting of selection and mutation, when the mutation rate is low and the populations are large.     

外商直接投资行业间技术溢出效应实证分析

文章选取1999~2003年的行业层面板数据,考察了FDI对中国工业部门内资企业生产率的影响。在考虑了多重共线性问题并控制住不可观测的时间效应和行业效应之后,研究结果显示,FDI产生了显著的行业内溢出和前向联系溢出,但后向联系溢出为负。此外,对技术差距最优区间的分析表明,当内资企业生产率为相应外资企业生产率的30%~70%时,前向联系溢出能实现最大化。     

蜈蚣博弈新视角——预期心理的应用

考虑到在蜈蚣博弈中运用逆推归纳法具有不稳定性以及混合策略的存在,无论是理性人假设发生偏离和理性人假设不发生偏离的情况下,逆推归纳法解蜈蚣博弈都具有不合理性。采用预期心理的方法可以预测蜈蚣博弈结果最有可能出现的结果。通过第三方的实验数据检验,蜈蚣博弈结果会以70 %的概率出现在预期心理预测的阶段。     

蜀葵组织培养与快繁体系建立

近年来北方对蜀葵的园林绿化需求越来越大,北方的环境条件不利于蜀葵的分株和扦插繁殖,急需建立蜀葵组培快繁体系;采用蜀葵无菌苗的茎段做为外植体对蜀葵进行离体快速繁殖,茎段接种4-5周直接诱导出不定芽,芽诱导培养基MS＋6-BA1mg/L为最佳;增值培养以MS＋6-BA2mg/L＋NAA1mg/L为好,其增殖系数较高,幼苗生长快而健壮;而根的诱导则以1/2MS＋蔗糖浓度10g/L相对理想。     

中国9大流域水利投入占用产出表的编制

首次提出了中国9大流域水利投入占用产出模型及中国9大流域水利投入占用产出表的编制方法。中国9大流域水利投入占用产出表反映了国民经济各部门对水利部门的资金、劳动力和各种商品及劳务的投入数量；反映了GDP增长与水利投资增加之间的关系；反映了流域水利建设对经济发展的拉动作用和保障作用。应用中国9大流域水利投入占用产出表计算了9大流域的用水系数、全部生产用水及工业用水的影子价格，提出了投资对增加值的后向总效应和后向净效应的概念及其计算方法，并计算了水利基建投资对国民经济的后向总效应和后向净效应。