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61.
This paper analyses the importance of openness for innovation in European regions. Openness is understood from a double angle: intercultural and scientific & technological. Our hypothesis is that each type of openness brings different kinds of knowledge into the regions and results on a different innovation output. S&T openness brings analytical forms of knowledge whilst intercultural openness brings tacit ones. Our results confirm this relationship as S&T openness shows a significant impact on patent activity, but not when a broader innovation indicator is used. Intercultural openness is highly significant when measuring innovation by a broader index and much less when measured by patents.  相似文献   
62.
Urbanization brings dramatic and sudden changes to ecological conditions affecting natural communities. Cavity-nesting birds, both primary and secondary (hereafter PCN and SCN, respectively), may be limited in this novel environment because of reduced abundance of nesting sites (e.g. snags and cavities) and competition for cavities with non-native species. But humans can also directly and indirectly provide nest sites (e.g., nest boxes, crevices on houses), especially for SCN species, potentially partially compensating for negative effects. We investigated whether and how PCNs and humans facilitated the cavity-nesting bird community along a gradient of urbanization. To do so, we estimated the abundance of cavity-nesting species between 1998 and 2010 at 135, 1-km2 sites that differed in the degree of urbanization (0–100 % forest cover). Also, we found 367 nests on a subset of 31 sites. PCNs (n = 67 nests) nested mostly on snags (98.5 %), while native SCNs (n = 141) used both natural (71.63 %) and anthropogenic (28.37 %) cavities. Non-native SCNs (n = 159 nests) used mostly anthropogenic cavities (98.11 %). PCN abundance facilitated native SCN abundance on sites with more than 12 % forest cover at 1-km2 scale, but not at less forested sites. There, native SCNs nested primarily (59 %) in anthropogenic cavities. Human facilitation allowed native SCNs to successfully use and reproduce where snags were scarce, changing the composition and structure of the cavity-nesting bird community within the most urbanized sites. Flexible nest site selection and human facilitation provide new opportunities for native cavity-nesting birds in a rapidly changing world.  相似文献   
63.
This article examines the demographic characteristics, motivations, and expectations of participants in a crowdsourced off-road traffic law reform in Finland. We found that the participants were mainly educated, full-time working professional males with a strong interest in off-road traffic. Though a minority, the women participating in the process produced more ideas than the men. The crowd was motivated by a mix of intrinsic and extrinsic factors. Intrinsic motivations included fulfilling civic duty, affecting the law for sociotropic reasons, to deliberate with and learn from peers. Extrinsic motivations included changing the law for financial gain or other benefits. Participation in crowdsourced policy-making was an act of grassroots advocacy, whether to pursue one’s own interest or more altruistic goals, such as protecting nature. The motivations driving the participation were in part similar to those observed in traditional democratic processes, such as elections as well as other online collaborations such as crowdsourced journalism and citizen science. The crowds’ behavior was, however, paradoxical. They participated despite the fact that they did not expect that their contributions would affect the law.  相似文献   
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The last decades have witnessed an increasing international concern in assessing how efficiently health care resources are used in producing health. At a country level, comparing the efficiency of regional health systems and ranking the regions accordingly promotes transparency policies and represents an important incentive for the design and implementation of specific programs aimed at improving the quality of health care services within the country. The use of data envelopment analysis (DEA) as a tool for efficiency analysis in the health sector is well-established, but its use with a ranking purpose is discouraged due to lack of discrimination and comparability issues. Using data from the competent health authority in Spain, the purpose of this study is to assess the efficiency of the regional health systems in Spain and identify those regions that are using their health care inputs more efficiently than others, given the observed level of health outcomes. To this aim, a DEA-based model that operates under a common weights basis is used in order to improve discrimination and establish a common scale for a proper comparison of the regional health systems in Spain that can be subsequently ranked by their efficiency score.  相似文献   
67.
Duplicate analysis is a strategy commonly used to assess precision of bioanalytical methods. In some cases, duplicate analysis may rely on pooling data generated across organizations. Despite being generated under comparable conditions, organizations may produce duplicate measurements with different precision. Thus, these pooled data consist of a heterogeneous collection of duplicate measurements. Precision estimates are often expressed as relative difference indexes (RDI), such as relative percentage difference (RPD). Empirical evidence indicates that the frequency distribution of RDI values from heterogeneous data exhibits sharper peaks and heavier tails than normal distributions. Therefore, traditional normal-based models may yield faulty or unreliable estimates of precision from heterogeneous duplicate data. In this paper, we survey application of the mixture models that satisfactorily represent the distribution of RDI values from heterogeneous duplicate data. A simulation study was conducted to compare the performance of the different models in providing reliable estimates and inferences of percentile calculated from RDI values. These models are readily accessible to practitioners for study implementation through the use of modern statistical software. The utility of mixture models are explained in detail using a numerical example.  相似文献   
68.
Microdata are required to evaluate the distributive impact of the taxation system as a whole (direct and indirect taxes) on individuals or households. However, in European Union countries this information is usually distributed into two separate surveys: the Household Budget Surveys (HBS), including total household expenditure and its composition, and EU Statistics on Income and Living Conditions (EU-SILC), including detailed information about households'' income and direct (but not indirect) taxes paid. We present a parametric statistical matching procedure to merge both surveys. For the first stage of matching, we propose estimating total household expenditure in HBS (Engel curves) using a GLM estimator, instead of the traditionally used OLS method. It is a better alternative, insofar as it can deal with the heteroskedasticity problem of the OLS estimates, while making it unnecessary to retransform the regressors estimated in logarithms. To evaluate these advantages of the GLM estimator, we conducted a computational Monte Carlo simulation. In addition, when an error term is added to the deterministic imputation of expenditure in the EU-SILC, we propose replacing the usual Normal distribution of the error with a Chi-square type, which allows a better approximation to the original expenditures variance in the HBS. An empirical analysis is provided using Spanish surveys for years 2012–2016. In addition, we extend the empirical analysis to the rest of the European Union countries, using the surveys provided by Eurostat (EU-SILC, 2011; HBS, 2010).  相似文献   
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Transportation and Migrant Adjustment in Georgia   总被引:2,自引:0,他引:2  
Access to transportation is critical for functioning in modern American society, and minorities disproportionately lack access to transportation. Latinos in Georgia—most of whom are newcomers to this country—are considerably less likely than non-Latino whites to drive alone to and from work because they do not live in households with a car available for personal use. We propose that this factor, along with limited access to alternative modes of transportation, impedes the ability of Georgia’s newest Latino residents to adjust to their new environment. In this study, we examine the impact of limited transportation options on the adjustment experience of recent Latino migrants to Georgia. We document how lack of personal transportation lends itself to a number of social problems including inability to obtain different work or to take advantage of opportunities for advancement. For Latinos who are both recent migrants to Georgia and recent immigrants to the United States, lack of transportation creates an adjustment “bottleneck,” whereby various paths to adaptation are simultaneously impeded. We argue that improving access to driver’s licenses, pedestrian infrastructure, and, in some places, public transportation should be a policy priority for states adjusting to recent influxes of Latino migrants.
Jorge H. AtilesEmail:
  相似文献   
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