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51.
Data from the 2004 Survey of Economic and Financial Aspects of Aging in Malaysia were analyzed to determine factors associated with self-reported health status among older Malaysians. Odds of self-reporting health as bad versus moderate or good were higher for respondents who were in lower income quintiles, who perceived their financial situation as bad, who were older and who were not married. Malay, Chinese, Indian, and Bumiputra ethnic groups had lower odds of perceiving their health to be bad as compared with those in other ethnic groups.  相似文献   
52.
In this paper, and based on a progressive type-II censored sample from the generalized Rayleigh (GR) distribution, we consider the problem of estimating the model parameters and predicting the unobserved removed data. Maximum likelihood and Bayesian approaches are used to estimate the scale and shape parameters. The Gibbs and Metropolis samplers are used to predict the life lengths of the removed units in multiple stages of the progressively censored sample. Artificial and real data analyses have been performed for illustrative purposes.  相似文献   
53.
In this paper, we introduce a new risk measure, the so‐called conditional tail moment. It is defined as the moment of order a ≥ 0 of the loss distribution above the upper α‐quantile where α ∈ (0,1). Estimating the conditional tail moment permits us to estimate all risk measures based on conditional moments such as conditional tail expectation, conditional value at risk or conditional tail variance. Here, we focus on the estimation of these risk measures in case of extreme losses (where α ↓0 is no longer fixed). It is moreover assumed that the loss distribution is heavy tailed and depends on a covariate. The estimation method thus combines non‐parametric kernel methods with extreme‐value statistics. The asymptotic distribution of the estimators is established, and their finite‐sample behaviour is illustrated both on simulated data and on a real data set of daily rainfalls.  相似文献   
54.
In this article, we derive exact expressions for the single and product moments of order statistics from Weibull distribution under the contamination model. We assume that X1, X2, …, Xn ? p are independent with density function f(x) while the remaining, p observations (outliers) Xn ? p + 1, …, Xn are independent with density function arises from some modified version of f(x), which is called g(x), in which the location and/or scale parameters have been shifted in value. Next, we investigate the effect of the outliers on the BLUE of the scale parameter. Finally, we deduce some special cases.  相似文献   
55.
Recent promotion of city centre living within UK policy has led to a commensurate interest in city centre conditions and the opinions and experiences of the people who live there. An apposite, straightforward method to capture city centre residents' experiences and views is described in this article. We successfully combined a novel, under‐utilized visual technique (self‐directed photography) with qualitative methods (log‐sheets and interviews) in the form of a ‘photo‐survey’. A background to visual methodologies is presented in this article, alongside a critique of using the photo‐survey with 84 city centre residents to investigate environmental conditions and perceptions within three of the UK's major cities. The method provided a rich, detailed set of data, but also brought a number of noticeable benefits to the data collection process. The photo‐survey not only effectively captured and documented life in the city but also acted as an ‘agent for change’, evoking thoughts and feelings which ultimately encouraged participants to reflect on their existing perceptions and urban experiences. The study also raises some important considerations for future work undertaken with this method and with using photographs as a set of data, and proposes techniques for minimising potential problems.  相似文献   
56.
Ali MM  Cleland J  Shah IH 《Demography》2003,40(4):659-673
Using "calendar" data for single women aged 15-24 from successive Demographic and Health Surveys (DHS) conducted in Colombia and Peru during the 1990s, we document trends, year by year, in sexual activity, the use of contraceptives, and subsequent reproductive outcomes. We provide evidence of the important and hitherto largely untapped potential of DHS calendar data to draw complete sexual and reproductive profiles when data from various surveys are integrated. Over the period 1985-1999, young single women in both Colombia and Peru became sexually active at younger ages. The use of contraceptives, especially the use of condoms, increased but did not fully offset the rise in sexual activity, and thus the incidence of premarital conceptions rose among young single women. In both countries, sharp declines occurred in the proportion of premaritally conceived births that were reported as being wanted.  相似文献   
57.
Pregnancy Wantedness And Maternal Behavior During Pregnancy   总被引:10,自引:1,他引:10  
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58.
Analysis of incomplete durations with application to contraceptive use   总被引:1,自引:0,他引:1  
Models for analysing incomplete durations obtained from cross-sectional surveys are presented. The aim of the paper is to develop a framework for analysing the incomplete duration of episodes in progress at the time of the survey by formulating generalized linear models and fitting and assessing them by using standard statistical packages. The maximum quasi-likelihood method is used for model fitting. The choice of the distribution and the diagnostic procedures are discussed. Simulated data from two distributions (the Weibull and log-logistic distributions) are used to evaluate the methodology developed and to assess model misspecifications. A data set on the current use of the contraceptive pill from a cross-sectional survey in Egypt is analysed.  相似文献   
59.
It is well known that standard asymptotic theory is not applicable or is very unreliable in models with identification problems or weak instruments. One possible way out consists of using a variant of the Anderson–Rubin ((1949), AR) procedure. The latter allows one to build exact tests and confidence sets only for the full vector of the coefficients of the endogenous explanatory variables in a structural equation, but not for individual coefficients. This problem may in principle be overcome by using projection methods (Dufour (1997), Dufour and Jasiak (2001)). At first sight, however, this technique requires the application of costly numerical algorithms. In this paper, we give a general necessary and sufficient condition that allows one to check whether an AR‐type confidence set is bounded. Furthermore, we provide an analytic solution to the problem of building projection‐based confidence sets from AR‐type confidence sets. The latter involves the geometric properties of “quadrics” and can be viewed as an extension of usual confidence intervals and ellipsoids. Only least squares techniques are needed to build the confidence intervals.  相似文献   
60.
International trade in Syria is highly regulated through a combination of tariffs and non-tariff barriers. At 8% of the value of imports on average, effective tariffs are relatively low. However, non-tariff barriers to trade actually make Syria's trade restrictiveness very high. Comparing world and domestic prices of imports indeed suggests that non-tariff barriers increase the domestic price of imported goods by 17% on average, notably the result of significant quantitative restrictions. Using a computable general equilibrium model, the costs of NTBs on the Syrian economy are assessed. Simulations suggest that reallocation gains resulting from a complete removal of NTBs could be substantial. Accordingly, the key message from the analysis is that trade reform if it focuses only on tariff reduction will have limited growth benefits. On the contrary, if the Government abolishes the widespread non-tariff barriers to trade, including the elimination of quantitative trade restrictions, trade policy can become the central instrument to redress Syria's growth prospects.  相似文献   
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