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101.
Using the behavioral model for health care use and unique data from the Mexican migration project, we explore the factors associated with hospital use among Mexican male migrants to the US. Twenty-eight percent of the respondents reported receiving healthcare from a hospital. In addition to established enabling factors of time in the US and English language ability, this research points to the importance of family social networks as enabling hospital health care use among migrants. Migrants with more ties to family members with migration experience have an increased likelihood of using emergency room healthcare. The research adds to the body of literature by providing evidence that ties to individuals with US migration experience increases migrants’ probability of accessing healthcare at hospitals.  相似文献   
102.
Abstract

When the mixed chart proposed by Aslam et al. (2015 Aslam, M., M. Azam, N. Khan, and C.-H. Jun. 2015. A mixed control chart to monitor the process. International Journal of Production Research 53 (15):468493. doi:10.1080/00207543.2015.1031354.[Taylor & Francis Online], [Web of Science ®] [Google Scholar]) is in use, the sample items are classified as defective or not defective and, depending on the number of defectives, the quality characteristic X of the sample items are also measured. In this case, an Xbar chart decides the state of the process. The previous conforming/non-conforming classification truncates the X distribution and, because of that, the mathematical development to obtain the ARLs is complex. Aslam et al. (2015 Aslam, M., M. Azam, N. Khan, and C.-H. Jun. 2015. A mixed control chart to monitor the process. International Journal of Production Research 53 (15):468493. doi:10.1080/00207543.2015.1031354.[Taylor & Francis Online], [Web of Science ®] [Google Scholar]) didn’t pay attention to the fact that the X distribution is truncated and, due to that, they obtained incorrect ARLs.  相似文献   
103.
In the framework of inequality measures decompositions, this article introduces an immediate and straightforward simplification for the Gini index when a population is divided in two subgroups. Since one of the key points in inequality analysis is represented by the role of overlapping units, a simulation study is developed in order to analyze the effects of the overlapping component on inequality decomposition. Simple expressions for the measurement of either overlapping component and inequality between are derived, which allow to correctly evaluate and compare the effects of different factors on total inequality.  相似文献   
104.
设计在巴塞罗那的生活中具有重要作用.在过去的几百年当中,设计是促进巴塞罗那产生创造力的背后推动力. 大约一百年前,我们在巴塞罗那开展了总体设计,比较著名的设计师有高迪以及和他同期的设计师.  相似文献   
105.
106.
We examine whether firms learn from their major acquisition failures. Drawing from a threat‐rigidity theoretical framework, we suggest that firms do not learn from their major acquisition failures. Furthermore, we hypothesize that host‐country experience reinforces the negative effects of major acquisition failures. Our research hypotheses are tested using an event history analysis of 741 acquisitions undertaken by French listed and non‐listed firms in the USA between January 1988 and December 2008. We use failure divestment (divestment resulting from acquisition failure) as a proxy for acquisition performance. Consistent with our theoretical framework, we find that major acquisition failures have a negative impact on future acquisition performance. Furthermore, we find that such negative effects are reinforced by firms’ host‐country experience.  相似文献   
107.
An explanatory model of adolescent problem behavior (problem drinking, cigarette smoking, and general delinquency) based on protective and risk factors in the individual and in 4 social contexts (family, peer group, school, and neighborhood) is employed in school‐based samples from the People's Republic of China (N=1,739) and the United States (N=1,596). Despite lower prevalence of the problem behaviors in the Chinese sample, especially for girls, a substantial account of problem behavior is provided by the same protective and risk factors in both countries and for both genders. Protection is generally higher in the Chinese sample than in the U.S. sample, but in both samples protection also moderates the impact of risk. Despite mean differences in psychosocial protective and risk factors, as well as in problem behavior, in the 2 samples—differences that may reflect societal variation—the explanatory model has, to a large extent, cross‐national generality.  相似文献   
108.
Randomizing the order of experimentation in a factorial design does not always achieve the desired effect of neutralizing the influence of unknown factors. In fact, with some very reasonable assumptions, an important proportion of random orders achieve the same degree of protection as that obtained by experimenting in the design matrix standard order. In addition, randomization can induce a large number of changes in factor levels and thus make experimentation expensive and difficult. De Leon et al. [Experimentation order in factorial designs with 8 or 16 runs, J. Appl. Stat. 32 (2005), pp. 297–313] proposed experimentation orders for designs with eight or 16 runs that combine an excellent level of protection against the influence of unknown factors, with the minimum number of changes in factor levels. This article presents a new methodology to obtain experimentation orders with the desired properties for designs with any number of runs.  相似文献   
109.
Let X be a discrete time contact process (CP) on ?2, as defined by Durrett and Levin (1994, Stochastic spatial models: a user's guide to ecological applications. Philosophical Transactions of the Royal Society of London Series B, 343, 329–350). We study the estimation of the model based on space-time evolution of X, that is, T + 1 successive observations of X on a finite subset S of sites. We consider the maximum marginal pseudo-likelihood (MPL) estimator and show that, when T→∞, this estimator is consistent and asymptotically normal for a non-vanishing supercritical CP. Numerical studies confirm these theoretical ones.  相似文献   
110.
In this paper we perform inference on the effect of a treatment on survival times in studies where the treatment assignment is not randomized and the assignment time is not known in advance. Two such studies are discussed: a heart transplant program and a study of Swedish unemployed eligible for employment subsidy. We estimate survival functions on a treated and a control group which are made comparable through matching on observed covariates. The inference is performed by conditioning on waiting time to treatment, that is, time between the entrance in the study and treatment. This can be done only when sufficient data are available. In other cases, averaging over waiting times is a possibility, although the classical interpretation of the estimated survival functions is lost unless hazards are not functions of waiting time. To show unbiasedness and to obtain an estimator of the variance, we build on the potential outcome framework, which was introduced by J. Neyman in the context of randomized experiments, and adapted to observational studies by D.B. Rubin. Our approach does not make parametric or distributional assumptions. In particular, we do not assume proportionality of the hazards compared. Small sample performance of the estimator and a derived test of no treatment effect are studied in a Monte Carlo study.  相似文献   
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