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A recent meta-analysis performed by Wellman, Cross, and Watson clears the air surrounding young children's performance on tests of false belief by showing that it is highly likely that there is some type of conceptual development between 3 and 5 years of age that supports improved task performance. The data concerning the evolutionary origin of these abilities, however, is considerably less clear. Nonetheless, there is some reason to suspect that theory of mind is unique to our species, and that its original function was to provide a more abstract level of describing ancient behavioral patterns (such as deception, reconciliation, and gaze following)-behaviors that humans share in common with many other species. Thus, the initial selective advantage of theory of mind may have been because it increased the flexibility of already-existing behaviors, not because it generated scores of radically new ones. 相似文献
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PURPOSE: The study seeks to determine how medical library professionals performing information-technology (IT) roles are compensated and how their positions are designed compared to information technology staff in their institutions. METHODS: 550 medical library directors in hospital and academic medical libraries were surveyed. The data was then compared to survey data from other compensation studies of the IT industry. RESULTS: There is a gap in compensation between medical library professionals and IT professionals performing similar functions using information technology. Technology-intense library jobs are compensated at higher levels than more traditional jobs. CONCLUSIONS: To compete with IT salaries, managers of medical library professionals will need to be ever more cognizant of the employment practices of IT professionals in nonmedical library disciplines. It is typically in the medical library's best interest to ensure that IT-related jobs, accountabilities, and capabilities of the medical library are known and understood by others, especially in the human resources and information technology staff departments. 相似文献
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Helmer D Savoie I Green C Kazanjian A 《Bulletin of the Medical Library Association》2001,89(4):346-352
BACKGROUND: Cochrane-style systematic reviews increasingly require the participation of librarians. Guidelines on the appropriate search strategy to use for systematic reviews have been proposed. However, research evidence supporting these recommendations is limited. OBJECTIVE: This study investigates the effectiveness of various systematic search methods used to uncover randomized controlled trials (RCTs) for systematic reviews. Effectiveness is defined as the proportion of relevant material uncovered for the systematic review using extended systematic review search methods. The following extended systematic search methods are evaluated: searching subject-specific or specialized databases (including trial registries), hand searching, scanning reference lists, and communicating personally. METHODS: Two systematic review projects were prospectively monitored regarding the method used to identify items as well as the type of items retrieved. The proportion of RCTs identified by each systematic search method was calculated. RESULTS: The extended systematic search methods uncovered 29.2% of all items retrieved for the systematic reviews. The search of specialized databases was the most effective method, followed by scanning of reference lists, communicating personally, and hand searching. Although the number of items identified through hand searching was small, these unique items would otherwise have been missed. CONCLUSIONS: Extended systematic search methods are effective tools for uncovering material for the systematic review. The quality of the items uncovered has yet to be assessed and will be key in evaluating the value of the systematic search methods. 相似文献
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Culture not only justifies the existence of libraries but also determines the level of funding libraries receive for development. Cultural appreciation of the importance of libraries encourages their funding; lack of such appreciation discourages it. Medical library development is driven by culture in general and the culture of physicians in particular. Nineteenth-century North American medical library funding reflected the impact of physician culture in three phases: (1) Before the dawn of anesthesia (1840s) and antisepsis (1860s), when the wisdom of elders contained in books was venerated, libraries were well supported. (2) In the last third of the nineteenth century, as modern medicine grew and as physicians emphasized the practical and the present, rather than books, support for medical libraries declined. (3) By the 1890s, this attitude had changed because physicians had come to realize that, without both old and new medical literature readily available, they could not keep up with rapidly changing current clinical practice or research. Thus, "The Medical Library Movement" heralded the turn of the century. 相似文献
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In this paper, we identify appropriate statistical methods for analysing categorical differences in discrete variables or 'performance indicators' resulting from performance analysis. The random mechanisms associated with discrete events do not follow a normal distribution; that is, the normal distribution is a continuous not a discrete probability distribution. We propose appropriate statistical methods based on two key discrete probability distributions, the Poisson and binomial distributions. Two approaches are proposed and compared using examples from notational analysis. The first approach is based on the classic chi-square test of significance (both the goodness-of-fit test and the test of independence). The second approach adopts a more contemporary method based on log-linear and logit models fitted using the statistical software GLIM. Provided relatively simple one-way and two-way comparisons in categorical data are required, both of these approaches result in very similar conclusions. However, as soon as more complex models or higher-order comparisons are required, the approach based on log-linear and logit models is shown to be more effective. Indeed, when investigating those factors and categorical differences associated with binomial or binary response variables, such as the proportion of winners when attempting decisive shots in squash or the proportion of goals scored from all shots in association football, logit models become the only realistic method available. By applying log-linear and logit models to discrete events resulting from notational analysis, greater insight into the underlying mechanisms associated with sport performance can be achieved. 相似文献