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Studies Examining (studies + examining)
Selected AbstractsA framework for cross-disciplinary team learning and performancePERFORMANCE IMPROVEMENT QUARTERLY, Issue 3 2008Scott P. Schaffer The construct of teamwork has been of considerable interest to researchers and practitioners across domains. The literature on teams includes many studies related to team composition, processes, and roles, but it pays much less attention to how teams learn and innovate. Studies examining how cross-disciplinary teams interact during projects are even less common. The study examined here was conceived to fill the need for a theoretical framework to describe how individuals from different disciplines evolve into a team that creates new forms of knowledge and innovative solutions or products. The framework, which was validated in a university service-learning program with over 25 teams, is a comprehensive theory merging two existing team models within a sociocultural system framework emphasizing the mediating aspects of the collective team and context. The theoretical foundations, the definitions, and dimensions of the framework are presented in this article. [source] Effects of terrestrial pollutants on insect parasitoids,ENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 6 2009Casey D. Butler Abstract Parasitoids are important organisms in the regulation of insect herbivores in natural, urban, and agricultural ecosystems. The impact of pollutants acting on parasitoids has not been extensively reviewed. This prompted us to propose a falsifiable null hypothesis (pollutants have no effects on parasitoids) and two alternative hypotheses (pollution negatively or positively affects parasitoids) to assess in the available literature the effects of pollutants acting on parasitoids. We found 26 studies examining 39 biological systems that met our criteria for inclusion. Of these studies, 18 of the 39 biological systems (46.2%) supported the null hypothesis while 18 (46.2%) supported the first alternative hypothesis in which pollutants exhibited negative effects on parasitoids. Only a small percentage of the studies (7.6%, 3 of 39) supported the second alternative hypothesis suggesting that pollutants had positive effects on parasitoids. We provide a synthesis of the available data by pollution type, summarize trends for different pollutants, and suggest future areas of research. [source] Judges' Use of Examinee Performance Data in an Angoff Standard-Setting Exercise for a Medical Licensing Examination: An Experimental StudyJOURNAL OF EDUCATIONAL MEASUREMENT, Issue 4 2009Brian E. Clauser Although the Angoff procedure is among the most widely used standard setting procedures for tests comprising multiple-choice items, research has shown that subject matter experts have considerable difficulty accurately making the required judgments in the absence of examinee performance data. Some authors have viewed the need to provide performance data as a fatal flaw for the procedure; others have considered it appropriate for experts to integrate performance data into their judgments but have been concerned that experts may rely too heavily on the data. There have, however, been relatively few studies examining how experts use the data. This article reports on two studies that examine how experts modify their judgments after reviewing data. In both studies, data for some items were accurate and data for other items had been manipulated. Judges in both studies substantially modified their judgments whether the data were accurate or not. [source] Effects of species diversity on the primary productivity of ecosystems: extending our spatial and temporal scales of inferenceOIKOS, Issue 3 2004Bradley J. Cardinale The number of studies examining how species diversity influences the productivity of ecosystems has increased dramatically in the past decade as concern about global loss of biodiversity has intensified. Research to date has greatly improved our understanding of how, when, and why species loss alters primary production in ecosystems. However, because experiments have been performed at rather small spatial and short temporal scales, it is unclear whether conclusions can be readily extrapolated to the broader scales at which natural communities are most likely to influence ecosystem functioning. Here we develop a simple patch-dynamics model to examine some of the scale-dependent and independent qualities of the diversity-productivity relationship. We first simulate a typical diversity-productivity experiment and show that the influence of species richness on productivity is temporally dynamic, growing stronger through successional time. This holds true irrespective of whether resource partitioning or a sampling effect is the underlying mechanism. We then increase the spatial scale of the simulation from individual patches to a region consisting of many patch types. Results suggest that the diversity-productivity relationship is not influenced by spatial scale per se, but that the mechanism producing the relationship can change from sampling effects within individual patches to resource partitioning across patch types composing the region. This change occurs even though model dynamics are the same at both scales, suggesting that sampling effects and resource partitioning can represent different descriptions of the same biological processes operating concurrently at differing scales of observation. Lastly, we incorporate regional processes of dispersal and disturbance into the model and show that these processes can amplify the effect of species richness on productivity, resulting in patterns not easily anticipated from experiments. We conclude that the relative control of community structure by local versus regional processes may be a primary determinant of the diversity-productivity relationship in natural ecosystems. Therefore, past experiments having focused only on local processes might not reflect patterns and processes underlying diversity-productivity relationships in communities where disturbance and dispersal regulate species biomasses. [source] Herding in online product choicePSYCHOLOGY & MARKETING, Issue 5 2006Jen-Hung Huang Previous research has shown that people are influenced by others when making decisions. This work presents three studies examining herding in product choices on the Internet. The first two studies addressed how two cues frequently found on the Internet, that is, sales volume and customer reviews, influence consumer on-line product choices. The third study examined the relative effectiveness of two recommendation sources. The experimental results revealed that subjects used the choices and evaluations of others as cues for making their own choices. However, herding effects are offset significantly by negative comments from others. Additionally, the recommendations of other consumers influence the choices of subjects more effectively than recommendations from an expert. Finally, implications of this work are discussed. © 2006 Wiley Periodicals, Inc. [source] DNA copy number alterations in prostate cancers: A combined analysis of published CGH studiesTHE PROSTATE, Issue 7 2007Jishan Sun Abstract BACKGROUND Identifying genomic regions that are commonly deleted or gained in neoplastic cells is an important approach to identify tumor suppressor genes and oncogenes. Studies in the last two decades have identified a number of common DNA copy number alterations in prostate cancer. However, because of various sample sizes, diverse tumor types and sources, as well as a variety of detection methods with various sensitivities and resolutions, it is difficult to summarize and fully interpret the overall results. METHODS We performed a combined analysis of all published comparative genomic hybridization (CGH) studies of prostate cancer and estimated the frequency of alterations across the genome for all tumors, as well as in advanced and localized tumors separately. A total of 41 studies examining 872 cancers were included in this study. RESULTS The frequency of deletions and gains were estimated in all tumors, as well as in advanced and localized tumors. Eight deleted and five gained regions were found in more than 10% of the prostate tumors. An additional six regions were commonly deleted and seven were commonly gained in advanced tumors. While 8p was the most common location of deletion, occurring in about a third of all tumors and about half of advanced tumors, 8q was the most commonly gained region, affecting about a quarter of all tumors and about half of all advanced tumors. CONCLUSIONS The large number of tumors examined in this combined analysis provides better estimates of the frequency of specific alterations in the prostate cancer cell genome, and offers important clues for prioritizing efforts to identify tumor suppressor genes and oncogenes in these altered regions. Prostate 67: 692,700, 2007. © 2007 Wiley-Liss, Inc. [source] | |||||||||||||