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31.
This paper addresses the role that scientific status plays in initial public offerings of technology focused firms. The paper builds on the literature of the sociology of science as well as the work of Spence (1974) and Podolny (1993) and argues that the presence of a Nobel laureate affiliated with a firm making an IPO provides a signal of firm quality to potential investors. Moreover, and building on the work of Podolny and Scott Morton (1999) and Stuart et al. (1999) we hypothesize that the importance of status diminishes as other measures of firm quality become available. We test our hypothesis for two periods of initial public offerings in biotechnology. We document that there is a clear difference in “maturity” of the firms across the two windows on a number of metrics. Consistent with our hypothesis that Nobel laureates play an important role as a non-financial signal of firm quality, we find that first-window firms with a Nobel laureate affiliate realize greater IPO proceeds in the amount of $24 million. In the second window the amount of money raised is not significantly different between Nobel and non-Nobel firms. This finding is consistent with the signaling literature that argues that the importance of a signal is inversely related to the availability of cogent information on firm quality. Consistent with this view, we also find a change between the two windows in the importance of other non-financial metrics used to convey value. Our research is one of the first to examine the dynamic nature of signals. Because we are unable to distinguish the extent to which the reduction in uncertainty at the firm level is correlated with the reduction of uncertainty at the industry level, the question remains as to the extent to which the diminished importance of signals in our second period is due to a change in market uncertainty versus a change in firm uncertainty.  相似文献   
32.
During backstroke, an optimum shoulder entry angle of 180° has been anecdotally suggested; however, this has yet to be investigated biomechanically. The aim of this study was to quantify shoulder entry angles for advanced and intermediate backstroke swimmers. Six advanced (season's best?<150?s) and six intermediate (season's best?>160?s) 200-m backstroke swimmers had markers applied to the medial humeral epicondyles and glenoid cavities. Following a familarization period, participants completed backstroke swimming trials (90?s each) in a swimming flume at 50%, 60%, 70%, and 80% of their season's best 200-m velocity. A camera positioned above the flume recorded frontal plane motion, which was digitized and analysed in Simi Motion Systems. The mean peak angle between the upper arm and the line of progression was established in ten strokes for each participant. The results showed backstroke shoulder entry angles for advanced swimmers (170°) were significantly closer to the suggested optimum 180° compared with those of intermediate swimmers (161°). The non-dominant arm displayed values closer to the optimum (171°), while swimming speed had no effect on backstroke shoulder entry angle. In conclusion, backstroke shoulder entry angle may help discriminate between advanced and intermediate backstroke swimmers and may be influenced by laterality dominance, being independent of swimming speed.  相似文献   
33.
This cohort study examined longitudinal changes in undergraduates' use of social media as information sources in academic and everyday-life contexts, covering types of social media used, purposes of use, and evaluation strategies. Web surveys were used, collecting data from 1,355 and 928 undergraduates in 2013 and 2019. The study found that students used most types of social media less in 2019 than 2013 in both contexts. Only media-sharing services bucked this downward pattern. Overall, a majority of social media types underwent changes in the top three purposes of use. The 2019 cohort used most evaluation strategies more frequently in both contexts. However, they favored simplistic strategies relying on superficial physical cues when evaluating information. Based on the findings, this study provided recommendations for information literacy education and interface design, such as covering multimedia information evaluation, leveraging various heuristics to prime careful use of social media and analytical evaluation of information.  相似文献   
34.
Education and Information Technologies - This paper is based on research studies conducted in the academic community of students and staff members (teachers, researchers and administrative staff)...  相似文献   
35.
自20世纪80年代中期以来,全世界范围内接连出现的政府主导的改革将高等教育系统向"教科书般"经济市场越推越近已实施的改革包括公司化、引入竞争性资助、增加学费和其他费用、使用高校管理中产出模式和绩效报告。但是,没有一个国家面向本国学生的第一学位教育是按照真正的资本主义经济市场来运作的,没有研究型大学的发展是被股东、利润、市场份额、配置效率或商品形式所驱动的。在一些国家,只有职业培训和国际教育才会真正收取商业性质的学费。虽然高等教育中普遍存在激烈的竞争、企业家精神和消费者话语,但资本主义在其中没有一席之地;现有的高等教育市场充其量是一个受监管的准市场在许多国家,高等教育领域的"市场改革"不同于交通、通信、广播电视和医疗保险界的私有化和商业化。究其原因,本文发现真正的市场改革受制于高等教育领域特定的内在限度(公共产品、地位竞争)以及与这些限度相关的政治因素、高等教育市场改革计划在本质上是乌托邦式的,目前市场改革的抽象理想仍在持续并不是因为它具有真正实现的前景,而是由于外源性政策的推动(如财政缩减、政府控制等)。如果资本主义市场是无法实现的,为什么要继续假装它们可以实现呢?我们需要一个与教育系... 更多还原  相似文献   
36.
This study analyzes degrees of differences between the private and public sectors of Polish higher education. It finds them to be strong: Polish private institutions function very differently from Polish public institutions and these differences correspond with those found in the literature on higher education elsewhere in the world. Polish intersectoral differences follow directions anticipated from the global literature. The study also provides material usable in policymaking by government agencies, public-private universities, and families.  相似文献   
37.
This study shows how the achievement of bilingual learners can be raised within the classroom context and within the framework of the National Curriculum. One text was used to stimulate a wide variety of language activities including using different styles and structures, having a sense of audience and an extended vocabulary, and exploring the children's own experiences and beyond.  相似文献   
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Many questions about picture interpretation behavior remain to be answered One question relates to the psychological nature of such behavior and may be stated; What psychological processes are involved in drawing inferences from pictures? This study attempts to answer the question using a model of picture interpretation that consists of two interdependent forms of behavior: observation and inference drawing. The study focuses on the latter, which is further divided into productive and evaluative processes. These are accounted for by three constructs: operational facility, the ability to generalize concepts, and conceptual fluency. To test the model and related hypotheses, two pictorial tests of inference drawing and 19 reference tests were administered to 95 children aged 10 to 12 years, A factor analytic methodology was employed.  相似文献   
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