锦江特大桥68+128+68m连续梁0#块托架设计研究

针对铜川—玉屏铁路线锦江特大桥68+128+68m连续梁0#块托架设计计算为工程实例,对连续梁0#块托架的设计计算过程进行了详尽的论述,并结合有限元仿真计算软件Midas对0#块托架各受力构件进行建模数值分析。表明:针对锦江特大桥68+128+68m连续梁0#块托架设计符合力学性能要求。     

Voting in assemblies of shareholders and incomplete markets

Summary. An economy with two dates is considered, one state at the first date and a finite number of states at the last date. Shareholders determine production plans by voting - one share, one vote - and at -majority stable stock market equilibria, alternative production plans are supported by at most percent of the shareholders. It is shown that a -majority stable stock market equilibrium exists if where S is the number of states at the last date and J is the number of firms. Moreover, an example shows that -majority stable stock market equilibria need not exist for smaller s.Received: 23 December 2002, Revised: 14 June 2004, JEL Classification Numbers: D21, D52, D71, G39. Correspondence to: Hervé CrésThe authors are grateful to an anonymous referee for helpful comments and suggestions. Financial support from the Danish Research Councils and hospitality of HEC is gratefully acknowledged by Mich Tvede and support from Fondation HEC is gratefully acknowledged by Hervé Crés.     

Efficient markets and Bayes’ rule

Summary. A series of financial anomalies motivated the development of new theories that modify the rational expectations ideal. Two possibilities have been systematically explored. The literature on behavioral finance relaxes the assumption that agents form beliefs according to the laws of probability and assume, instead, that simpler heuristic rules are used. Another stream of the literature assumes that agents process information according to Bayes rule, but do not posses sufficient information to know the true data generating process. In this paper, Bayesian and Behavioral agents coexist and trade in a standard dynamic asset pricing model. A long-standing conjecture is demonstrated. It is shown that, under suitable assumptions, Bayesian agents drive Behavioral, non-Bayesian agents out of the market. Hence, asset prices are eventually determined under the Bayesian paradigm.Received: 3 June 2004, Revised: 17 September 2004, JEL Classification Numbers: D83.Preliminary versions have circulated under the titles Markets Favor Bayesian Models and Market Selection of Empirical Models under Limited Information. I thank Larry Blume, David Easley, Larry Epstein, Armando Gomes, Bruce Hansen, Lars Hansen, Richard Kihlstrom, Grace Koo, George Mailath, Werner Ploberger, Andrew Postlewaite and Shakeeb Khan for useful comments. I also thank participants at the NBER GE meetings, Evolutionary Finance conference in Zurich, Latin American Meetings of the Econometric Society, Stanford Institute for Theoretical Economics, the Instituto de Matematica Pura e Aplicada, the theory seminar at Brown, Chicago, Harvard-MIT, Minnesota, Penn and Wisconsin. I gratefully acknowledge the financial support from the National Science Foundation Grant SES 0109650.     

Productivity and Employment in the Information Economy: What Kaldor’s and Verdoorn’s Growth Laws Can Teach the US

During the last decade of the 20th century the US economy experienced the longest economic boom since World War II. Information and communication technologies (ICT) are seen as one of the main reasons for this development and it is still an open question how ICT will affect growth and employment in the future. To evaluate this process Kaldors growth laws, especially Verdoorns law are reconsidered. It will be discussed which changes in the Verdoorn-Coefficient (VC) and the employment threshold (ET) can be expected due to ICT. Induced technical progress and increasing returns to scale could make future economic growth to be less labor-intensive. A simple OLS estimation using data for the US non-farm sector indicates that the VC increased in the second half of the 1990s. Thus, more output growth is required to keep employment constant.The author gratefully acknowledges the most valuable comments from two anonymous referees and the participants of the Annual Meeting of the Austrian Economic Association (NOeG) at the Vienna University of Economics (WU), May 21–22, 2004. Any remaining errors are my own.     

财政支农的市场一体化效应及其政策

以增加农民收入从而支撑具有产业、区域特征的市场一体化为视角,对财政政策不同的支农方式和支农工具所产生的不同的农业市场一体化效应进行了分析,认为直接收入补贴明显好于价格支持;间接支农优于直接支农;而且不同的支农项目对市场一体化的促进作用差异显著。为此,提出了逐步减少价格支持,增加直接收入补贴,增加财政间接支农力度,引导农业生产要素多渠道利用,促进农业系统内外部合作,重视三农无形资产,建立适当监督机制等政策建议。     

入世后金融创新的国际扩散对我国金融业的影响

在目前我国金融创新研发能力还比较低的情况下，通过扩散方式进行金融创新是我国金融创新的主要形式。对入世后金融创新国际扩散对我国金融业的影响进行了分析。     

On the evolutionary edge of altruism: a game-theoretic proof of Hamilton’s rule for a simple case of siblings

We offer a game-theoretic proof of Hamiltons rule for the spread of altruism. For a simple case of siblings, we show that the rule can be derived as the outcome of a one-shot prisoners dilemma game between siblings.JEL Classification: A13, C70, D64Correspondence to: Oded Stark, ZEF, University of Bonn, Walter-Flex-Strasse 3, 53113 Bonn, GermanyWe are indebted to an anonymous referee and to Uwe Cantner for helpful comments and suggestions. Partial financial support from the National Institute on Aging (grant RO1-AG13037) and from the Humboldt Foundation is gratefully acknowledged.     

Self-interest, sympathy and the origin of endowments

We explore whether the recent laboratory findings that suggest the origin of endowment matters in simple bargaining games are actually due to contextual shifts of relative effort and deservingness. Results support previous findings of endowment origin yielding more self-interested behavior.     

Tari–tax reforms and market access

Reducing taris and increasing consumption taxes is a standard IMF advice to countries that want to open up their economy without hurting government finances. Indeed, theoretical analysis of such a tari–tax reform shows an unambiguous increase in welfare and government revenues. The present paper examines whether the country that implements such a reform ends up opening up its markets to international trade, i.e. whether its market access improves. It is shown that this is not necessarily so. We also show that, comparing to the reform of only taris, the tari–tax reform is a less efficient proposal to follow both as far as it concerns market access and welfare.     

Information aggregation in financial markets with career concerns

What are the equilibrium features of a dynamic financial market in which traders care about their reputation for ability? We modify a standard sequential trading model to include traders with career concerns. We show that this market cannot be informationally efficient: there is no equilibrium in which prices converge to the true value, even after an infinite sequence of trades. We characterize the most revealing equilibrium of this game and show that an increase in the strength of the traders' reputational concerns has a negative effect on the extent of information that can be revealed in equilibrium but a positive effect on market liquidity.