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121.
Urban Ecosystems - Many European towns and cities have undergone reurbanisation processes in recent decades. However, their effects on urban biodiversity have been poorly studied. Currently...  相似文献   
122.
This paper presents and applies a methodology of socioeconomic classification that integrates asset- and social class approaches. We employ data from the 2013 Brazilian National Household Survey and use latent class analysis to identify clusters and classify the working population. With regard to social class the Brazilian occupations are classified based on the European Socioeconomic Classification (ESeC) schema and an indicator of employment status. As for household wealth, we use the items related to household condition, ownership of durable goods and access to public services with the highest discriminatory power. We also make use of variables that account for the Brazilian spatial and socio-demographic heterogeneity. We found four clusters which we term latent socioeconomic stratum (LSeS). When compared we found an ordered pattern from the best-off LSeS (1) to the worst-off (4) with respect to household wealth and ESeC classes. Nevertheless, although the class composition of each LSeS reveals a distinct concentration of specific ESeC classes, all classes are present in each LSeS. Controlling for social class, differences in household wealth are more marked between LSeS than between social classes within the same LSeS. Hence, the methodology unveils the latent socioeconomic strata, reveals a class schema for each stratum and points out potential stratum fractions within them. The results were validated using variables external to the model, namely household food security status and years of schooling. The external validation revealed the same ordered pattern and the presence of stratum fractions.  相似文献   
123.
This paper begins by identifying how, as a result of the confluence of a number of factors, civil organizations (COs) in Mexico have shown an exponential development in the past 15 years. However, it is argued that COs are suffering a fiscal crisis and, in some sense, an economic one, provoked by the political reaction of the government toward this growth. At the same time, there is no crisis of legitimacy; their increasing levels of social support suggests a trend in the reverse direction. However, the legitimacy attributable by the population to nonprofits seems to be due to the novelty of this sociopolitical actor in the context of a disappointment with more traditional ones including government and political parties—as opposed to an endorsement of their proven capacity or efficiency in solving the problems of development. To take advantage of what seems to be a golden opportunity for its positive development, in addition to changing the unfavorable economic environment, it is argued that the sector has to face the challenge of thinking in its long-term interest and making sure that it is positioned to act as capably efficient.  相似文献   
124.
Generalised variance function (GVF) models are data analysis techniques often used in large‐scale sample surveys to approximate the design variance of point estimators for population means and proportions. Some potential advantages of the GVF approach include operational simplicity, more stable sampling errors estimates and providing a convenient method of summarising results when a high number of survey variables is considered. In this paper, several parametric and nonparametric methods for GVF estimation with binary variables are proposed and compared. The behavior of these estimators is analysed under heteroscedasticity and in the presence of outliers and influential observations. An empirical study based on the annual survey of living conditions in Galicia (a region in the northwest of Spain) illustrates the behaviour of the proposed estimators.  相似文献   
125.
In this article we present a new composite index of child health, applied to the Least Developed Countries (LDCs) of Africa, one of the areas of the planet most castigated by poverty. Our index has been constructed attending to the variables defined in the Goals of the Millennium Declaration. For this purpose we will use the P2 distance method for the year 2008, the last year for which data are available. This index integrates variables of child health that permit a territorial ordering of the LDCs of Africa, in terms of those partial indicators.  相似文献   
126.
Throughout the human life span the functions of several physiological systems dramatically change, including proprioception. Impaired proprioception leads to less accurate detection of body position changes increasing the risk of fall, and to abnormal joint biomechanics during functional activities so, over a period of time, degenerative joint disease may result. Altered neuromuscular control of the lower limb and consequently poor balance resulting from changes in the proprioceptive function could be related to the high incidence of harmful falls that occur in old age subjects. There is evidence of proprioception deterioration with aging. Regular physical activity seems to be a beneficial strategy to preserve proprioception and prevent falls among older subjects. Some studies have demonstrated that the regular physical activity can attenuate age-related decline in proprioception. This paper reviews the evidence of age effects on joint proprioception. We will discuss the possible mechanisms behind these effects and the role of regular physical activity in the attenuation of age-related decline in proprioception.  相似文献   
127.
Relationships between species and their environment are a key component to understand ecological communities. Usually, this kind of data are repeated over time or space for communities and their environment, which leads to a sequence of pairs of ecological tables, i.e. multi-way matrices. This work proposes a new method which is a combined approach of STATICO and Tucker3 techniques and deals to the problem of describing not only the stable part of the dynamics of structure–function relationships between communities and their environment (in different locations and/or at different times), but also the interactions and changes associated with the ecosystems’ dynamics. At the same time, emphasis is given to the comparison with the STATICO method on the same (real) data set, where advantages and drawbacks are explored and discussed. Thus, this study produces a general methodological framework and develops a new technique to facilitate the use of these practices by researchers. Furthermore, from this first approach with estuarine environmental data one of the major advantages of modeling ecological data sets with the CO-TUCKER model is the gain in interpretability.  相似文献   
128.
To address the persistent problems of foodborne and zoonotic disease, public health officials worldwide face difficult choices about how to best allocate limited resources and target interventions to reduce morbidity and mortality. Data‐driven approaches to informing these decisions have been developed in a number of countries. Integrated comparative frameworks generally share three methodological components: estimating incidence of acute illnesses, chronic sequelae, and mortality; attributing pathogen‐specific illnesses to foods; and calculating integrated measures of disease burden such as cost of illness, willingness to pay, and health‐adjusted life years (HALYs). To discuss the similarities and differences in these approaches, to seek consensus on principles, and to improve international collaboration, the E.U. MED‐VET‐NET and the U.S.‐based Food Safety Research Consortium organized an international conference convened in Berlin, Germany, on July 19–21, 2006. This article draws in part on the deliberations of the conference and discusses general principles, data needs, methodological issues and challenges, and future research needs pertinent to objective data‐driven analyses and their potential use for priority setting of foodborne and zoonotic pathogens in public health policy.  相似文献   
129.
We introduce the doubly truncated function of indices, for discrete variables, and we obtain the inversion formula for the distribution function. Also, we characterize the geometric distribution using the left truncated function of indices.  相似文献   
130.
In this paper the most general bivariate distributions with second kind beta conditionals is fully characterized. This family is closed under inversions and the conditional moments are shown to be rational functions of the conditioned variable. Two subfamilies of dependent distributions is shown to have second kind beta marginals too. Finally, as a particular case, the most general bivariate distribution with second kind Pareto conditionals is characterized.  相似文献   
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