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11.
Urban growth is a major factor of global environmental change and has important impacts on biodiversity, such as changes in species composition and biotic homogenization. Most previous studies have focused on effects of urban area as a general measure of urbanization, and on few or single taxa. Here, we analyzed the impacts of the different components of urban sprawl (i.e., scattered and widespread urban growth) on species richness of a variety of taxonomic groups covering mosses, vascular plants, gastropods, butterflies, and birds at the habitat and landscape scales. Besides urban area, we considered the average age, imperviousness, and dispersion degree of urban area, along with human population density, to disentangle the effects of the different components of urban sprawl on biodiversity. The study was carried out in the Swiss Plateau that has undergone substantial urban sprawl in recent decades.Vascular plants and birds showed the strongest responses to urban sprawl, especially at the landscape scale, with non-native and ruderal plants proliferating and common generalist birds increasing at the expense of specialist birds as urban sprawl grew. Overall, urban area had the greatest contribution on such impacts, but additional effects of urban dispersion (i.e., increase of non-native plants) and human population density (i.e., increases of ruderal plants and common generalist birds) were found. Our findings support the hypothesis that negative impacts of urban sprawl on biodiversity can be reduced by compacting urban growth while still avoiding the formation of very densely populated areas.  相似文献   
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In confirmatory clinical trials, the prespecification of the primary analysis model is a universally accepted scientific principle to allow strict control of the type I error. Consequently, both the ICH E9 guideline and the European Medicines Agency (EMA) guideline on missing data in confirmatory clinical trials require that the primary analysis model is defined unambiguously. This requirement applies to mixed models for longitudinal data handling missing data implicitly. To evaluate the compliance with the EMA guideline, we evaluated the model specifications in those clinical study protocols from development phases II and III submitted between 2015 and 2018 to the Ethics Committee at Hannover Medical School under the German Medicinal Products Act, which planned to use a mixed model for longitudinal data in the confirmatory testing strategy. Overall, 39 trials from different types of sponsors and a wide range of therapeutic areas were evaluated. While nearly all protocols specify the fixed and random effects of the analysis model (95%), only 77% give the structure of the covariance matrix used for modeling the repeated measurements. Moreover, the testing method (36%), the estimation method (28%), the computation method (3%), and the fallback strategy (18%) are given by less than half the study protocols. Subgroup analyses indicate that these findings are universal and not specific to clinical trial phases or size of company. Altogether, our results show that guideline compliance is to various degrees poor and consequently, strict type I error rate control at the intended level is not guaranteed.  相似文献   
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Searches for faint signals in counting experiments are often encountered in particle physics and astrophysics, as well as in other fields. Many problems can be reduced to the case of a model with independent and Poisson-distributed signal and background. Often several background contributions are present at the same time, possibly correlated. We provide the analytic solution of the statistical inference problem of estimating the signal in the presence of multiple backgrounds, in the framework of objective Bayes statistics. The model can be written in the form of a product of a single Poisson distribution with a multinomial distribution. The first is related to the total number of events, whereas the latter describes the fraction of events coming from each individual source. Correlations among different backgrounds can be included in the inference problem by a suitable choice of the priors.  相似文献   
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We present tight upper and lower bounds for the traveling salesman path through the points of two-dimensional modular lattices. We use these results to bound the traveling salesman path of two-dimensional Kronecker point sets. Our results rely on earlier work on shortest vectors in lattices as well as on the strong convergence of Jacobi–Perron type algorithms.  相似文献   
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Graffiti is an illegitimate culture, yet with high potential for distinction and abstract aesthetic principles. The article considers these characteristics as result of the process of the autonomization of graffiti as subcultural field and aims to reconstruct its field logic.  相似文献   
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Latest developments in modern societies have altered living circumstances. Upcoming insecurities concerning employment and family relationships make life more and more incalculable. Especially young adults throughout the modern world are forced to rethink their life concepts and to desist from the lives of former generations. As difficulties to achieve a successful life increase, one could assume that the young are confronted with the impossibility of feeling happy and satisfied with their lives anymore. Yet, latest social surveys prove wrong. Although increasing unemployment, lower net income and single parenthood make life more difficult for the young, they still enjoy very high subjective quality of life in comparison to the older population. Throughout the paper I argue that it is not the objective conditions that make young adults (15–29 years old) feel overwhelmingly happy. Looking for other sources of explanation of high quality of life among people aged 29 or below, I argue for indicators of social embeddedness as being influential on their assessment of life. But again, the proportion of explained variance is smaller compared to older people. With the help of empirical data taken from the European Social Survey I highlight the differences in life circumstances between the young and the total population. Concerning occupation, habitation (kind of inhabited household) and financial situation, most of the young live under different situations compared to the adult world. But surprisingly, the rates of perceived high quality of life among the young do not vary to such a large extent as among the adults. I show that young adults, often damned to fail social demands because of their withdrawal from social life, are still the most happy in modern (more and more individualizing?) societies. But it gets more difficult to account for the reasons of their happiness.  相似文献   
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Relations between society and business are increasingly characterized by the societal demand for compliance with ethical standards. Companies are held responsible for behavior of their employees, which increases the demand for effective internal governance. To assure compliance, many companies enact codes of ethics. Despite a common core of ethical standards, codes differ considerably in formal design elements. Albeit theory suggests that a code's formal design, that is, how a code's content is presented, affects its behavioral impact, there is little research on this issue. Addressing this research gap, we conducted a between-subjects experiment (factorial survey) in which we manipulated design elements of codes and examined how these elements affect behavioral intentions in various business situations. Holding the code's content constant, we manipulated its tone (positive vs. negative) and whether it was signed by the company's executive board (with vs. without signature). Our results indicate that the effectiveness of a code can be improved by using signed codes, while there is no effect for a code's tone. Our paper contributes designing internal governance in two ways: by giving experimental evidence on the relevance of a code's formal design and by providing practical guidance how to increase code effectiveness.  相似文献   
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We consider social welfare functions that satisfy Arrow's classic axioms of independence of irrelevant alternatives and Pareto optimality when the outcome space is the convex hull of some finite set of alternatives. Individual and collective preferences are assumed to be continuous and convex, which guarantees the existence of maximal elements and the consistency of choice functions that return these elements, even without insisting on transitivity. We provide characterizations of both the domains of preferences and the social welfare functions that allow for anonymous Arrovian aggregation. The domains admit arbitrary preferences over alternatives, which completely determine an agent's preferences over all mixed outcomes. On these domains, Arrow's impossibility turns into a complete characterization of a unique social welfare function, which can be readily applied in settings involving divisible resources such as probability, time, or money.  相似文献   
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