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1.
Due to the paucity of sources of negative firm‐specific information, US capital markets have more difficulty identifying and incorporating bad news into stock prices than they do good news. Even though insider selling is a potentially important proxy for undisclosed bad news, researchers have difficulty ex ante identifying information‐based sales due to an inability to separate liquidity‐motivated from information‐based insider trades. We hypothesize that when insiders in multiple firms sell shares of one firm in which they are insiders and at the same time buy shares of other insider portfolio firms, the sale is more likely to be information‐based, since the proceeds are reinvested. Conversely, when an insider sells one firm without purchasing others or sells multiple insider firms the sale is likely liquidity‐motivated. We find that insider sales identified as information‐based using this algorithm are followed by significant negative abnormal returns. Information‐based sales are also more likely to be associated with delistings, earnings declines and earnings restatements. Analysts are also more likely to revise their earnings forecasts downwards for these firms. It is thus possible to ex ante identify insider sales with information content. Our results will be of interest to investors and also to regulators designing insider trading rules.  相似文献   
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Epiphytic macroinvertebrate communities of four coastal wetlands of Green Bay, Lake Michigan were compared by taxonomic composition, feeding group composition, and environmental influences using Bray-Curtis ordination. Ordination scores from the most sheltered oligotrophic site, Portage Marsh, were distinct from the eutrophic, exposed sites located in middle and lower Green Bay— Seagull Bar, Little Tail Point, and Dead Horse Bay. Epiphyton chlorophyll a, phytoplankton chlorophyll a, and specific conductance strongly correlated to the ordination axes, indicating the trophic gradient within Green Bay was a primary environmental influence. The feeding group compositions at the sites were consistent with the type and abundance of food available. Portage Marsh is a scraper-shredder system, with macroinvertebrates feeding mainly on epiphyton and coarse particulate detritus. Dead Horse Bay and Little Tail Point are collector systems, sustained by phytoplankton and fine particulate organic matter. Seagull Bar is intermediate in trophic position along the ordination axes, but more closely resemble the latter two sites. The type and abundance of food resources available to these invertebrate communities are influenced by wave exposure, light attenuation, nutrient levels, and algae levels of the littoral and pelagial waters. Macroinvertebrate communities were sensitive to shifts in food resources, which generated shifts in trophic structure.  相似文献   
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This paper presents the development andvalidation of new measurement tools to exploreself-efficacy toward service and toward civicparticipation. We developed and administereda survey to 851 students in an AACSB-accreditedcollege of business at a comprehensive publicuniversity located in the Midwest. Traditionalscale development methodologies plusconfirmatory factor analysis and simultaneousfactor analysis in several populations wereused to analyze both a primary sample and aholdback sample. Results strongly support thevalidity and reliability of the surveyinstrument. Future use for the instrumentincludes verification of the effectiveness ofpedagogies designed to increase self-efficacytoward service and motivation for civicparticipation in business students.  相似文献   
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阐述了水利水电施工企业项目管理的特点,就本施工企业实行项目管理的实践情况作了介绍,对施工企业如何进行规范化项目管理提出了建议。  相似文献   
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We provide a partial ordering view of horizontal inequity (HI), based on the Lorenz criterion, associated with different post‐tax income distributions and a (bistochastic) non‐parametric estimated benchmark distribution. As a consequence, several measures consistent with the Lorenz criterion can be rationalized. In addition, we establish the so‐called HI transfer principle, which imposes a normative minimum requirement that any HI measure must satisfy. Our proposed HI ordering is consistent with this principle. Moreover, we adopt a cardinal view to decompose the total effect of a tax system into a welfare gain caused by HI‐free income redistribution and a welfare loss caused by HI, without any additive decomposable restriction on the indices. Hence, more robust tests can be applied. Other decompositions in the literature are seen as particular cases.  相似文献   
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This article reviews the dynamic evolution of personality research and practice in work organizations from the early 1900s through the present. The article reveals steady‐state equilibrium in the world of practice. In contrast, the world of research is shown to be punctuated by rapid changes in conceptual foci, levels of analysis, and methodological approaches, as well as whether or not personality at work is even considered important. Explanations are offered for these trends, including the ways theory and research in the larger world of the study of personality have been reflected in personality research in and on work organizations. The article concludes with some thoughts about revisiting various branches in this evolution and suggestions for the future of personality research and practice in work organizations. © 2007 Wiley Periodicals, Inc.  相似文献   
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孙德炳  狄正莹  边文 《价值工程》2021,40(35):107-109
白鹤滩水电站大坝施工共用7台缆机,但因缆机电气室降温系统规划布置不完善,易造成缆机电气室内温度高而导致电器模块、机构故障,影响缆机运行,为优化缆机电气室降温系统,通过对缆机电气室及ABB柜顶部增设散热装置,外墙增加隔热反光板,空调外机移位,并采用智能降温系统控制等方法,使缆机电气室内高温得到解决,降低因温度过高造成电器元件故障,保证缆机安全、平稳运作,节省设备维修成本,可为同类工程提供参考.  相似文献   
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图尔古松水电站位于东哈萨克斯坦州济良诺夫斯克西北30 km处,其深孔弧形闸门除承受高水头的静水压力、地震动水压力,还需考虑泥沙淤积以及温度变化的影响。弧形闸门是电站泄洪、排砂的主要控制设备,根据其受力与止水特点及环境特性,弧门设计采用主横框架结构,直支臂支撑,顶止水为P型和转铰止水双重水封,设计为温度-51~40℃,除考虑材料热胀冷缩的影响,还设计了有效的融冰措施,可满足挡水、运行和检修要求。  相似文献   
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