Gender differences in willingness to compete: The role of public observability

A recent literature emphasizes that gender differences in the labor market may in part be driven by a gender gap in willingness to compete. However, whereas experiments in this literature typically investigate willingness to compete in private environments, real world competitions often have a more public nature, which introduces potential social image concerns. If such image concerns are important, and men and women differ in the degree to which they want to be seen as competitive, making tournament entry decisions publicly observable may further exacerbate the gender gap. We test this prediction using a laboratory experiment (N = 784) that varies the degree to which the decision to compete, and its outcome, is publicly observable. We find that public observability does not alter the magnitude of the gender gap in willingness to compete in an economically or statistically significant way.     

Cognitive abilities,self-efficacy,and financial behavior

This paper investigates the effect of cognitive abilities on financial behavior among older adults. Using the U.S. Health and Retirement Study, I find that cognitive abilities significantly affect financial behavior through two channels: ability and self-efficacy. People with higher cognition scores achieve better financial outcomes. This positive association is especially strong in tasks having high demand of cognitive abilities, which confirms the ability channel of the cognitive ability effect. In addition, there is evidence for the self-efficacy channel as a secondary source of cognitive influence. Lower cognitive abilities decrease people’s sense of self-efficacy, which, in turn, significantly decreases financial management efficiency. The findings have important policy implications, specifically that more effort is needed to assist the growing older population through the cognitive aging process and that noncognitive skills, as a secondary source of influence, also warrant attention.     

Spatial variation in soil inorganic nitrogen across an arid urban ecosystem

We explored variations in inorganic soil nitrogen (N) concentrations across metropolitan Phoenix, Arizona, and the surrounding desert using a probability-based synoptic survey. Data were examined using spatial statistics on the entire region, as well as for the desert and urban sites separately. Concentrations of both NO₃-N and NH₄-N were markedly higher and more heterogeneous amongst urban compared to desert soils. Regional variation in soil NO₃-N concentration was best explained by latitude, land use history, population density, along with percent cover of impervious surfaces and lawn, whereas soil NH₄-N concentrations were related to only latitude and population density. Within the urban area, patterns in both soil NO₃-N and NH₄-N were best predicted by elevation, population density and type of irrigation in the surrounding neighborhood. Spatial autocorrelation of soil NO₃-N concentrations explained 49% of variation among desert sites but was absent between urban sites. We suggest that inorganic soil N concentrations are controlled by a number of ‘local’ or ‘neighborhood’ human-related drivers in the city, rather than factors related to an urban-rural gradient.     

Lower bounds on expectations of positive L-statistics from without-replacement models

We consider samples drawn without replacement from finite populations. We establish optimal lower non-negative and upper non-positive bounds on the expectations of linear combinations of order statistics centered about the population mean in units generated by the population central absolute moments of various orders. We also specify the general results for important examples of sample extremes, Gini mean differences and sample range. The paper completes the results of Papadatos and Rychlik [2004. Bounds on expectations of L-statistics from without replacement samples. J. Statist. Plann. Inference 124, 317–336], where sharp negative lower and positive upper bounds on the expectations of the combinations were presented for the without-replacement samples.     

数控机床功能的扩展

本文主要分析了HEIDENHAIN TNC 310数控铣床系统中圆弧铣削指令及螺纹铣削指令,对螺纹铣削功能进行延伸,扩展到圆弧三轴联动,并对螺纹铣削指令格式进行了修改,从而具有圆弧三轴联动铣削功能。     

Cognitive and interpersonal abilities related to the primary activities of R&D managers

This study attempted to identify the primary activities performed by R&D managers at different supervisory levels, and the cognitive and interpersonal ability requirements that underlie these activities. A task inventory containing 244 managerial tasks was completed by 117 R&D managers in nine organizations. The 48 tasks which managers rated as having spent the most time were factor analyzed, resulting in the identification of three primary activities: project management, personnel supervision, and strategic planning. Furthermore, these activities varied with supervisory level, with R&D managers performing a wider range of these activities with the progression from first-line to upper-level management.Thirty R&D managers later rated the degree to which 19 cognitive and interpersonal abilities were required for performing these primary activities. Strategic planning was rated as requiring significantly higher levels of oral expression, logical reasoning, originality, fluency of ideas, oral defense, and resistance to premature judgement than was required for the other two primary activities. Personnel supervision required a higher level of social sensitivity than was required for the other two activities. Project management required high levels of information ordering, oral fact- finding ability, problem sensitivity, and oral and written comprehension. Implications of the findings for understanding R&D managerial performance and personnel staffing functions are discussed.     

论虚拟企业经营中的问题及对策

企业的"虚拟化经营"已有各种形式并得到良好发展,虚拟企业在新的市场环境下形成了自己独特的竞争优势,但在实际运作中也存在着一些问题,如目标利益的差异性、缺乏制度约束,企业文化的兼容、核心技术的流失以及各组成部分实体上的管理和协调上的困难等等,针对这些问题,需要研究一系列切实有效的对策.     

R＆D经费投入的国际比较与借鉴

R&D经费投入是评价国家科技实力和科技发展水平的首选指标 ,长期以来已为世界各国和重要国际组织所普遍采用。本文主要针对我国R&D经费投入与国际间的比较 ,分析我国R&D投入所处的阶段及R&D投入方面存在的差距与困难 ,最后提出对策与建议     

新硼试剂3—甲氧基—甲亚胺H与硼显色反应的研究

对新硼试剂3-甲氧基-甲亚胺H与硼显色反应体系研究结果表明,在pH=5的醋酸-醋酸铵缓冲体系中,硼与3-甲氧基-甲亚胺H在常温下形成2:3的黄绿色配合物,配合物稳定24h以上,λmax=410nm,ε550=6.82×104cm·mol-1·L-1,硼含量在0～2.5μg/25mL范围符合比耳定律.     

虚拟企业是21世纪企业的主流模式

在 2 1世纪市场竞争日益激烈 ,市场需求日趋多样化、用户化 ,新型的企业模式———虚拟企业必将代替传统的企业模式。本文界定了虚拟企业的涵义 ,介绍了虚拟企业的产生 ,分析了虚拟企业的特点 ,阐述了虚拟企业的经营方式 ,最后探讨了如何构建虚拟企业。