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In the economic and social aftermath of the 2008 crisis there has been an important and growing new wave of highly qualified Portuguese emigration comprising scientists. No or very few public policies have been designed to reverse this phenomenon, risking the consequences of brain drain. International literature argues that professional reasons are central to scientists’ decision to migrate, even after the 2008 crisis. Spending some time in a foreign country to study, research, or teach, is perceived as a common step in an individual academic trajectory and an advantage for a successful professional career in academia. It is also encouraged by European Union policies. Twelve individual portraits of Portuguese scientists living in central Europe reveal how important other factors are to the migration decision‐making process. These factors include the economic crisis, student mobility programmes, and the current Portuguese scientific system revision.  相似文献   
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This paper uses a novel approach to infer hospital technical quality from revealed preferences over residency programs. Specifically, we use Spanish medical graduates’ residency choices made from 1995 to 2000. We start by estimating a model of medical graduates preferences that controls for hospital, proximity, specialty, and gender effects. We interpret the coefficients on the hospital dummy variables as measures of medical graduates’ preferences over hospitals. Our results show that graduates do indeed discriminate between hospitals and that their preferences correlate with hospital‐specific covariates arguably related to hospital training quality. We then show that preferences from medical graduates are positively and statistically significantly correlated with risk‐adjusted hospital rankings based on five alternative outcome measures. Finally, we construct reputation scores for each hospital using news story counts in three media outlets and find that medical graduates’ preferences are especially valuable for inference of hospital technical quality of care as they do not simply reflect well known reputation.  相似文献   
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There is an increasing interest in multimodal technology-based warnings, namely those conveying speech-warning statements. This type of warning may be tailored to the situation as well as to the target user's characteristics. However, more information is needed on how to design these warnings in a way that ensures intelligibility, promotes compliance and reduces the potential for annoyance. In this context, this paper reports an exploratory study whose main purpose was to assist the selection of a synthesized voice for a subsequent compliance study with personalized (i.e., using the person's name) technology-based warnings using Virtual Reality. Participants were requested to listen to speech signals, gathered from a speech synthesizer and post-processed in order to change the pitch perception, and then these were evaluated by fulfilling the MOS-X questionnaire. After that, the participants ranked the voices according to their preference. The effects of the speaker's gender and voice pitch, on both ratings and ranking were assessed. The preference of the male and female listeners for a talker's voice gender was also investigated. The results show that participants mostly prefer as first choice the high-pitched female voice, which also gathered the highest overall score in the MOS-X questionnaire. No significant influence of the participants' gender was found on the assessed measures.  相似文献   
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For the univariate case, the R chart and the S 2 chart are the most common charts used for monitoring the process dispersion. With the usual sample size of 4 and 5, the R chart is slightly inferior to the S 2 chart in terms of efficiency in detecting process shifts. In this article, we show that for the multivariate case, the chart based on the standardized sample ranges, we call the RMAX chart, is substantially inferior in terms of efficiency in detecting shifts in the covariance matrix than the VMAX chart, which is based on the standardized sample variances. The user's familiarity with sample ranges is a point in favor of the RMAX chart. An example is presented to illustrate the application of the proposed chart.  相似文献   
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This article seeks to measure deprivation among Portuguese households, taking into account four well-being dimensions – housing, durable goods, economic strain and social relationships – with survey data from the European Community Household Panel. We propose a multi-stage approach to a cross-sectional analysis, side-stepping the sparse nature of the contingency tables caused by the large number of variables considered and bringing together partial and overall analyses of deprivation that are based on Bayesian latent class models via Markov Chain Monte Carlo methods. The outcomes demonstrate that there was a substantial improvement on household overall well-being between 1995 and 2001. The dimensions that most contributed to the risk of household deprivation were found to be economic strain and social relationships.  相似文献   
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Pollen dispersal in tropical seed plants is established mainly by biotic vectors, both in intact and fragmented environments. In urban landscapes, the segregation of natural remnants by an artificial matrix can reduce pollinator foraging efficiency. It is unknown how nectarivorous bats, regarded as long-distance pollen dispersers, respond to such habitat structure combined with city-related factors. Here, we investigated the pollen dispersal pattern between spatially segregated individuals of the bat-pollinated Bignoniaceae Crescentia cujete within an urban environment. From 2015 to 2017, we assessed their spatiotemporal structure, breeding system and annual fruit set in order to relate these factors to the bat activity in the region. We employed fluorescent dyes as pollen analogues to infer the role of bats in pollen flow. Adding to the low density of individuals, we found a low daily flower emission and low flowering synchrony (S?=?0,092), all of which are traits that favor outcrossing. Individuals were distributed in two distant groups (>600 m), with no occurrence of dye flow between them. In contrast, flow within the same individual was intense, which points toward bats’ territorial behavior. C. cujete is self-compatible, but not autogamous; therefore, despite few outcross events, bats could be ensuring the plant’s year-round fruit production mainly through self-pollination. Our findings show restricted bat foraging extent, which affects overall pollen dispersal distance and population connectivity. These results can be extrapolated to natural metapopulations inserted in an urban matrix and serve as a groundwork for studying directly the effect of city-related factors on pollinator behavior.

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