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181.
182.
Armando Serrano‐Lombillo Ignacio Escuder‐Bueno Manuel G. de Membrillera‐Ortuño Luis Altarejos‐García 《Risk analysis》2011,31(6):1000-1015
In the past few years, the field of dam safety has approached risk informed methodologies throughout the world and several methodologies and programs are appearing to aid in the systematization of the calculations. The most common way of implementing these calculations is through the use of event trees, computing event probabilities, and incremental consequences. This methodology is flexible enough for several situations, but its generalization to the case of systems of several dams is complex and its implementation in a completely general calculation methodology presents some problems. Retaining the event tree framework, a new methodology is proposed to calculate incremental risks. The main advantage of this proposed methodology is the ease with which it can be applied to systems of several dams: with a single risk model that describes the complete system and with a single calculation the incremental risks of the system can be obtained, being able to allocate the risk of each dam and of each failure mode. The article shows how both methodologies are equivalent and also applies them to a case study. 相似文献
183.
It is argued that migration from Mexico to the US and return migration are determined by international wage differentials
and preferences for origin. We use a model of job search, savings and migration to show that job turnover is a crucial determinant
of the migration process. We estimate this model by Simulated Method of Moments (SMM) and find that migration practically
disappears, it goes down from 19 to 0.5%, had Mexico US arrival rates while employed. A lower decrease in migration, to 7%,
occurs by an increase in Mexican wage offers. On the other hand, doubling migration costs reduces migration rates from 19
to 5%, while subsidizing return migration in $300 reduces migration rates only to 14%. 相似文献
184.
Victor M. Guerrero 《统计学通讯:理论与方法》2013,42(21):4568-4585
We consider the problem of estimating a trend with different amounts of smoothness for segments of a time series subjected to different variability regimes. We propose using an unobserved components model to consider the existence of at least two data segments. We first fix some desired percentages of smoothness for the trend segments and deduce the corresponding smoothing parameters involved. Once the size of each segment is chosen, the smoothing formulas here derived produce trend estimates for all segments with the desired smoothness as well as their corresponding estimated variances. Empirical examples from demography and economics illustrate our proposal. 相似文献
185.
186.
J.M. Muñoz Pichardo J. Muñoz García J.M. Fernández Ponce M.D. Jiménez Garnero 《统计学通讯:理论与方法》2013,42(3):529-547
In this paper we obtain several influence measures for the multivariate linear general model through the approach proposed by Muñoz-Pichardo et al. (1995), which is based on the concept of conditional bias. An interesting charasteristic of this approach is that it does not require any distributional hypothesis. Appling the obtained results to the multivariate regression model, we obtain some measures proposed by other authors. Nevertheless, on the results obtained in this paper, we emphasize two aspects. First, they provide a theoretical foundation for measures proposed by other authors for the mul¬tivariate regression model. Second, they can be applied to any linear model that can be formulated as a particular case of the multivariate linear general model. In particular, we carry out an application to the multivariate analysis of covariance. 相似文献
187.
188.
Leonor Gallardo Pablo Burillo Marta García-Tascón Juan J. Salinero 《Social indicators research》2009,94(2):297-317
Sports facility planning by the public authorities should be considered to be one of the main policies to have an indirect
influence on the aim of ensuring a healthy population, as well as reducing its physical inactivity. Our research aims to study
and compare the state of sports infrastructures in the regions of Spain, using a synthetic indicators. Our results should
serve not only to detect the vast imparity between different regions, which has come about because of varying investment and
management with regard to sports infrastructures, but also to redirect building planning and sports management policies onto
the right path, and also give food for thought. 相似文献
189.
Mixtures of truncated exponentials (MTE) potentials are an alternative to discretization and Monte Carlo methods for solving
hybrid Bayesian networks. Any probability density function (PDF) can be approximated by an MTE potential, which can always
be marginalized in closed form. This allows propagation to be done exactly using the Shenoy-Shafer architecture for computing
marginals, with no restrictions on the construction of a join tree. This paper presents MTE potentials that approximate standard
PDF’s and applications of these potentials for solving inference problems in hybrid Bayesian networks. These approximations
will extend the types of inference problems that can be modelled with Bayesian networks, as demonstrated using three examples. 相似文献
190.
José María Sarabia Enrique Castillo Marta Pascual María Sarabia 《Journal of Economic Inequality》2007,5(3):371-383
In this paper, the most general bivariate distribution with lognormal conditionals is fully characterized, using the methodology
proposed by [3]. The properties of the new family are studied in detail, including marginal and conditional distributions, regression functions,
dependence measures, moments and inequality measures. The new distribution is very broad, and contains as a particular case
the classical bivariate lognormal distribution. Several subfamilies are studied and a generalization of the basic model is
discussed. Finally, we present an empirical application. We estimate and compare the basic model proposed in the paper with
a classical model, using data from the European Community Household Panel in different periods of time. 相似文献