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571.

In many European countries requirements for retirement have been tightened, causing an increase in work participation of older workers, in spite their potentially poorer health may limit their work ability. This study aimed at assessing the diffusion of health problems and exposure to unfavorable working conditions among ageing workers in two Italian surveys, as well as comparing them with those observed in the same surveys conducted before the 2011 Italian pension reform tightening the normal retirement age. The 2013 National Health Survey (NHS) and Labour Force Survey (LFS) were employed to assess the prevalence of poor perceived health, health conditions and functional limitations, and of exposure to physical, psychosocial and organization factors at work, among 60–64 years workers. Poisson regression models were used to estimate Prevalence Ratios of health outcomes and unfavorable working conditions in the two surveys, compared to data from the 2005 (NHS) and 2007 (LFS) corresponding surveys, respectively. Among both men and women, approximately one quarter had at least one physical disorder or functional limitations and 15% poor mental health. Exposure to different ergonomic factors (15–30%) and working during unsocial hours (19%) were particularly diffused. A significant increase in the prevalence of functional limitations and of working at night or during unsocial hours was found in 2013, compared to corresponding data from 2005 and 2007, respectively. Our results indicate that exposure to ergonomic and organizational hazards should be reduced among ageing workers, to avoid decreased work ability, health damage or early exit from the labour market.

  相似文献   
572.
The health of older immigrants can have important consequences for needed social support and demands placed on health systems. This paper examines health differences between immigrants and the native-born populations aged 50 years and older in 11 European countries. We examine differences in functional ability, disability, disease presence and behavioral risk factors, for immigrants and non-immigrants using data from the Survey of Health, Aging and Retirement in Europe (SHARE) database. Among the 11 European countries, migrants generally have worse health than the native population. In these countries, there is a little evidence of the "healthy migrant" at ages 50 years and over. In general, it appears that growing numbers of immigrants may portend more health problems in the population in subsequent years.  相似文献   
573.
Public Organization Review - This article assesses the level of transparency of epidemiological and financial budgetary information on the COVID-19 pandemic in Brazilian state governments and the...  相似文献   
574.
Journal of Combinatorial Optimization - The Angular Constrained Minimum Spanning Tree Problem ( $$\alpha $$ -MSTP) is defined in terms of a complete undirected graph $$G=(V,E)$$ and an angle...  相似文献   
575.
In this paper four regression estimators are considered for a finite population total based on interpenetrating subsamples, two of which are with jackknifing and the other two are without jackknifing. Both theoretical and empirical comparisons of the four proposed estimators are done with respect to bias, variance and mean square error.  相似文献   
576.
The main purpose of this paper is the longitudinal analysis of the poverty phenomenon. By interpreting poverty as a latent variable, we are able to resort to the statistical methodology developed for latent structure analysis. In particular, we propose to use the mixture latent Markov model which allows us to achieve two goals: (i) a time-invariant classification of households into homogenous groups, representing different levels of poverty; (ii) the dynamic analysis of the poverty phenomenon which highlights the distinction between transitory and permanent poverty situations. Furthermore, we exploit the flexibility provided by the model in order to achieve the measurement of poverty in a multidisciplinary framework, using several socio-economic indicators as covariates and identifying the main relevant factors which influence permanent and transitory poverty. The analysis of the longitudinal data of the Survey on Households Income and Wealth of the Bank of Italy provides the identification of two groups of households which are characterized by different dynamic features. Moreover, the inclusion of socio-economic covariates such as level of education, employment status, geographical area and residence size of the household head shows a direct association with permanent poverty.  相似文献   
577.
ABSTRACT

The procedure for online control by attribute consists of inspecting a single item at every m items produced (m ≥ 2). On each inspection, it is determined whether the fraction of the produced conforming items decreased. If the inspected item is classified as non conforming, the productive process is adjusted so that the conforming fraction returns to its original status. A generalization observed in the literature is to consider inspection errors and vary the inspection interval. This study presents an extension of this model by considering that the inspected item can be rated independently r (r ≥ 1) times. The process is adjusted every time the number of conforming classifications is less than a, 1 ≤ a ≤ r. This method uses the properties of an ergodic Markov chain to obtain the expression for the average cost of this control system. The genetic algorithm methodology is used to search for the optimal parameters that minimize the expected cost. The procedure is illustrated by a numerical example.  相似文献   
578.
In this work, a generalization of the Goodman Association Model to the case of q, q > 2, categorical variables which is based on the idea of marginal modelling discussed by Gloneck–McCullagh is introduced; the difference between the proposed generalization and two models, previously introduced by Becker and Colombi, is discussed. The Becker generalization is not a marginal model because it does not imply Logit Models for the marginal probabilities, and because it is based on the conditional approach of modelling the association. The Colombi model is only partially a marginal model because it uses simple logit models for the univariate marginal probabilities but is based on the conditional approach of modelling the association. It is also shown that the maximum likelihood estimation of the parameters of the new model is feasible and, to compute the maximum likelihood estimates, an algorithm is proposed, which is a numerically convenient compromise between the constrained optimization approach of Lang and the straightforward use of the Fisher Scoring Algorithm suggested by Glonek–McCullagh.Finally, the proposed model is used to analyze a data set concerning work accidents which occurred to workers at some Italian firms during the years 1994–1996.  相似文献   
579.
ABSTRACT

This article proposes a method to estimate the degree of cointegration in bivariate series and suggests a test statistic for testing noncointegration based on the determinant of the spectral density matrix for the frequencies close to zero. In the study, series are assumed to be I(d), 0 < d ? 1, with parameter d supposed to be known. In this context, the order of integration of the error series is I(d ? b), b ∈ [0, d]. Besides, the determinant of the spectral density matrix for the dth difference series is a power function of b. The proposed estimator for b is obtained here performing a regression of logged determinant on a set of logged Fourier frequencies. Under the null hypothesis of noncointegration, the expressions for the bias and variance of the estimator were derived and its consistency property was also obtained. The asymptotic normality of the estimator, under Gaussian and non-Gaussian innovations, was also established. A Monte Carlo study was performed and showed that the suggested test possesses correct size and good power for moderate sample sizes, when compared with other proposals in the literature. An advantage of the method proposed here, over the standard methods, is that it allows to know the order of integration of the error series without estimating a regression equation. An application was conducted to exemplify the method in a real context.  相似文献   
580.
In this article we consider a control chart based on the sample variances of two quality characteristics. The points plotted on the chart correspond to the maximum value of these two statistics. The main reason to consider the proposed chart instead of the generalized variance | S | chart is its better diagnostic feature, that is, with the new chart it is easier to relate an out-of-control signal to the variables whose parameters have moved away from their in-control values. We study the control chart efficiency considering different shifts in the covariance matrix. In this way, we obtain the average run length (ARL) that measures the effectiveness of a control chart in detecting process shifts. The proposed chart always detects process disturbances faster than the generalized variance | S | chart. The same is observed when the size of the samples is variable, except in a few cases in which the size of the samples switches between small size and very large size.  相似文献   
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