Race and STEM Degree Attainment

This paper reviews the key literature on racial disparities in entry and persistence to attain a STEM bachelor's degree. Overall, the literature provides quite consistent evidence that Black and Hispanic students are well represented in college major choices in STEM, which testifies to the interest of racial minorities in STEM fields. However, they are left behind during college, and many are left without a STEM degree or any degree whatsoever. We emphasize that although racial minority students may seem to be left behind during college in STEM fields, the problem dates further back to pre‐college. We need to examine college and pre‐college studies in an integrative manner, in order to achieve full understanding and come up with the right solution to the problem of racial disparity in STEM attainment.     

流通产业的改革与发展:一个理论前瞻

本文给出了一个描述商品流通企业生存发展条件的简单模型.通过模型分析指出商品流通企业改革与发展的中心,是降低进货价和经营成本,同时设法提高商品的效用与附加值.文章最后以此为理论依据,对我国商品流通产业的组织、业态、区域分布等方面的改革发展趋势进行了初步预测.     

General Probability‐Time Tradeoff and Intertemporal Risk‐Value Model

This article proposes an intertemporal risk‐value (IRV) model that integrates probability‐time tradeoff, time‐value tradeoff, and risk‐value tradeoff into one unified framework. We obtain a general probability‐time tradeoff, which yields a formal representation form to reflect the psychological distance of a decisionmaker in evaluating a temporal lottery. This intuition of probability‐time tradeoff is supported by robust empirical findings as well as by psychological theory. Through an explicit formalization of probability‐time tradeoff, an IRV model taking into account three fundamental dimensions, namely, value, probability, and time, is established. The object of evaluation in our framework is a complex lottery. We also give some insights into the structure of the IRV model using a wildcatter problem.     

基于完全竞争的生物质制氢产业市场结构分析

相对化石能源,生物质氢能源是一种理想的可再生能源,由于尚未形成有效的产业化市场价格机制,其产业化应用进展缓慢,对此,本文从完全竞争市场模型出发分析其产业化的理论机理。首先,建立了完全竞争的生物质制氢厂商的社会福利优化模型,然后,讨论了优化模型解的两个条件,进一步得出了生物质制氢厂商利润最大化的条件。在此基础上,从增加生物质制氢供给,降低厂商研发成本角度提出了初步的政策建议。     

比较视域中的庄子与尼采生命自由思想

生命自由是庄子与尼采哲学的主旨。从比较视域审视,庄子与尼采的生命自由都同样立足于生命本体意义的观照,强调生命本真的守持与人格的独立,追求个性自由的充分彰显。但因各自所处时代、地域与文化的截然不同,他们的生命自由思想在缘起、内涵解读、实现方式以及终极诉求等方面相应地呈现出"离乱之世"与"工业社会"、"超脱"与"创造"、"忘"与"变"以及"真人"与"超人"等巨大反差,体现了两者的不同生命旨趣与价值祈求。     

Strengthening the understanding of the relationship between survival designs and test statistics

In the planning of randomized survival trials, the role of follow‐up time of trial participants introduces a level of complexity not encountered in non‐survival trials. Of the two commonly used survival designs, one design fixes the follow‐up time whereas the other allows it to vary. When the follow‐up time is fixed the number of events varies. Conversely, when the number of events is fixed, the follow‐up time varies. These two designs influence test statistics in ways that have not been fully explored resulting in a misunderstanding of the design–test statistic relationship. We use examples from the literature to strengthen the understanding of this relationship. Group sequential trials are briefly discussed. When the number of events is fixed, we demonstrate why a two‐sample risk difference test statistic reduces to a one‐sample test statistic which is nearly equal to the risk ratio test statistic. Some aspects of fixed event designs that need further consideration are also discussed. Copyright © 2009 John Wiley & Sons, Ltd.     

我国利率降低的效应分析

:利率是资金的价格 ,也是一个重要的经济杠杆 ,对经济起着主要的调节作用。同时 ,利率也作为中央银行的货币政策工具之一 ,在近几年的宏观调控中发挥着较大的作用。特别是近几年 ,我国的连续几次降息 ,给我国经济带来很大的影响。但由于我国的一些特殊原因 ,使几次降息的效应没有显现出来。基于此 ,以及其他原因 ,要求利率在今后的一段时期内应保持不变 ,才能适应经济发展的要求     

科恩的归纳支持分级理论及其背景分析

进入20世纪后,人们不再把归纳法作为发现的方法,而是当作检验或评价假说的逻辑.在这种情形下,为了克服帕斯卡概率归纳逻辑理论面临的困难,重建排除归纳法并且对归纳逻辑进行辩护,试图在局部归纳逻辑的框架内解决休谟问题,科恩提出了他的归纳支持分级理论.     

驳中国文化不能产生逻辑学论——再次与程中棠教授商榷

程中棠教授文章所谓"中国文化不能产生逻辑学",其论点不当之处,论述如下:1.希腊哲学是奴隶主的哲学,希腊逻辑产生于意识形态领域阶级斗争的表现--"百家争鸣".2.一个国家把政治、道德放在第一位,并不排斥逻辑学的产生.3.不同的阶级、派别有不同的政治要求和善恶观念,并不妨碍他们有共同的逻辑学.4.<小取>是逻辑学,并非意识形态著作;墨子的"兼爱"与"杀盗"并非互相冲突的政治主张;<小取>"杀盗非杀人"的论证并非诡辩.5."程文"关于"逻辑思想"的解释是混淆概念.6."程文"为了论证中国古代无逻辑学不惜贬斥中国古代的逻辑思维和文化是不正确的.