Random Walks and Market Efficiency Tests of Latin American Emerging Equity Markets: A Revisit

The few existing studies on equity price dynamics and market efficiency for Latin American emerging equity markets show conflicting results. This study uses multiple varianceratio and auto-regressive fractionally integrated moving-average tests and new data (U.S. dollar-based national equity indices for the 1987–1997 period) to clarify these results. Documented evidence shows that equity prices in major Latin American emerging equity markets — Argentina, Brazil, Chile and Mexico—follow a random walk, and that they are, generally, weak-form efficient. In sum, therefore, the evidence suggests that international investors in these markets cannot use historical information to design systematically profitable trading schemes because future long-term returns are not dependent on past returns.     

Entrepreneurial resource acquisition via personal networks: an empirical study of German start-ups

This paper presents a resource-based theoretical model for an extended version of the network success hypothesis. It derives four main hypotheses for the relationships between resources obtained from personal networks of the founders and a new venture's success. The model takes into account a broad range of control variables. In the empirical study, based on a sample of 123 German entrepreneurs, we do not find much support for our hypotheses. We conclude that, quite in contrast to most existing theories, network links have close to no impact on getting cheap or exclusive resources.     

Conservatism in residual income models: theory and supporting evidence

In this paper, we develop a framework for evaluating the impact of conservative accounting on the structure of residual income models of equity valuation. We explore specific examples of both unconditional and conditional conservatism and observe a common mathematical structure. We proceed to generalise our model and identify the joint dependency of conservatism and the persistence of abnormal earnings on the weights attached to book values, earnings and dividends. We are able to show theoretically the likely numerical impact of conservatism on price-earnings ratios and under-valuations produced by residual income models. We investigate empirically the interaction between conservatism and persistence and find they accord well with the theory developed. We briefly discuss the implications of testing the effect of conservatism on valuation and linear information dynamics.     

谈企业运输单车承包

根据企业运输面临的困境，阐述了企业运输的改革思路，单车利润承包是企业运输改革发展的产物，也是整体扭亏解困的重要途径，以及单车承包措施等。     

轮胎使用年限及我国轮胎报废量预测研究

给出了轮胎平均使用年限和轮胎报废量计算方法。依据统计数据计算,我国汽车和摩托车外胎使用年限平均为1.9年和2.7年。测算废汽车和摩托车外胎重量为10 kg和1 kg左右。2011~2015年全国及各省市废轮胎产生量逐年增加,废汽车外胎占废轮胎总量的90%以上,是废轮胎回收的重点。     

A novel methodology for designing a household waste collection system for insular zones

This paper addresses the problem of designing a household waste collection system for rural insular areas using a barge for transportation, based on a novel mixed integer programming model that simultaneously integrates decisions of waste collection sites selection within the islands to be served, visit schedule for each selected collection site, and multi-period vehicle routing. An application to a real-world instance consisting of small rural islands located in the south of Chile shows the effectiveness and complexity of the model, along with the advantages of using a waste compactor instead of transporting the waste using bins onboard a barge.     

以基础设施建设推动我国城市交通的发展

文章从城市道路建设和城市交通工具的发展两个方面描述了我国城市交通发展的现状，分析了目前我国城市交通发展所面临的问题。同时提出了加强以交通工具建设、道路建设和政策法规建设为主的城市交通基础设施建设，来缓解我国城市交通中所面临的问题。最后说明了加强基础设施建设在我国城市发展过程中的重要意义。     

Gibbsian and non-Gibbsian states at Eurandom

We review some of the work on non-Gibbsian states of the last 10 years, emphasizing the developments in which Eurandom played a role.     

Groups Formation and Operations in the Web 2.0 Environment and Social Networks

The Internet and the Web are evolving to a platform for collaboration, sharing, innovation and user-created content—the so-called Web 2.0 environment. This environment includes social and business networks, and it is influencing what people do on the Web and intranets, individually and in groups. This paper describes the Web 2.0 environment, its tools, applications, characteristics. It also describes various types of online groups, especially social networks, and how they operate in the Web 2.0 environment. Of special interest is the way organization members communicate and collaborate mainly via wikis and blogs. In addition, the paper includes a proposed triad relational model (Technology–People–Community) of social/work life on the Internet. Particularly, social/work groups are becoming sustainable because of the incentives for participants to connect and network with other users. A discussion of group dynamics that is based on the human needs for trust, support, and sharing, regardless if the setting is a physical or virtual one, follows. Finally, future research directions are outlined.