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321.
Child maltreatment cases involving substance abuse have increased. Estimates reveal that between 40% and 80% of all families involved with child protection have substance-abuse issues. Only 12%-20% of substance-abusing families regain custody of their children. Little is known about the factors that contribute to substance-abusing women regaining or losing custody of their children. Using the Multiple Embedded Case Study method, this study illuminates the experiences and feelings of mothers struggling to overcome addiction and highlights the main differences between women who regained custody and those who permanently lost custody of their children. In this study, 50% of the women lost custody and 50% regained custody of their children. The women who lost custody of their children tended to be in survival mode, characterized as going through the motions, engaging in acting-out behaviors, and failing to follow treatment recommendations. The women who regained custody of their children tended to thrive, characterized as having internal motivation, taking responsibility, and engaging the material. This study advances our knowledge of the factors contributing to reunification. Understanding these factors can lead to the development of practices that increase the likelihood of reunification for families struggling to overcome addiction.  相似文献   
322.
Previous studies of smoking risk beliefs have focused almost exclusively on risks to the smoker. Using an original set of survey data from Spain, we examine the public's perceived risks from exposures to environmental tobacco smoke. The risk categories considered included lung cancer, heart disease, life expectancy loss, and low birth weight for children of smoking mothers. Risk beliefs were quite high, often dwarfing scientific estimates of the risk. The results are consistent with overestimation of risks from highly publicized, low probability events.  相似文献   
323.
This paper is centred on the analysis of the information embedded in the optimal weights of the assets in the CAPM and the Bamberg–Dorfleitner model. On this basis, first we find a functional relationship between the optimal weights of both models. Next, we find a set of performance indicators that express the contribution of each asset to the reward/volatility ratio measured as the Sharpe ratio or through a utility function. For the Bamberg–Dorfleitner model these indicators also lead to identify the contribution of each independent variable to the reward/volatility ratio. Technically, these connections are obtained through the covariance-normalized portfolio that consists of a transformation of the inverted covariance matrix. The additive property of covariances is transmitted to the indicators. These results enable investors and portfolio managers to obtain a precise knowledge of the causes of the value of the reward/volatility ratio. From the corporate point of view, this approach contributes to a better identification of the features of the different types of investors to whom to focus the corporate financial policy.  相似文献   
324.
Xiong  Yi  Braun  W. John  Hu  X. Joan 《Lifetime data analysis》2021,27(3):388-412
Lifetime Data Analysis - Understanding the distribution of an event duration time is essential in many studies. The exact time to the event is often unavailable, and thus so is the full event...  相似文献   
325.

This research presents the results of two related studies on the convergent and construct validity of three measures of reciprocity in exchange relationships at work. In Study 1, 71 Dutch teachers were interviewed about their specific investments and outcomes in the exchange relationships with their students, colleagues and school. ANOVA revealed that they reported significantly more investments than outcomes, and that the number of reported investments and outcomes mentioned varied as a function of the type of exchange relationship. Building on these results, multi-item scales were created to assess reciprocity at a detailed level for each of the three exchange relationships. Study 2 validated these specific reciprocity measures by relating them to two global assessments of reciprocity (convergent validity) as well as to measures of job stress and well-being (construct validity). LISREL-analysis of data obtained from a further sample of 224 teachers revealed that for each type of exchange relationship there were significant, consistent and meaningful relationships among the three reciprocity measures. Further, hierarchical regression analysis showed that the reciprocity measures were differentially related to job stressors and measures of well-being. Implications are discussed.  相似文献   
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This article explores Bayesian joint models of event times and longitudinal measures with an attempt to overcome departures from normality of the longitudinal response, measurement errors, and shortages of confidence in specifying a parametric time-to-event model. We allow the longitudinal response to have a skew distribution in the presence of measurement errors, and assume the time-to-event variable to have a nonparametric prior distribution. Posterior distributions of the parameters are attained simultaneously for inference based on Bayesian approach. An example from a recent AIDS clinical trial illustrates the methodology by jointly modeling the viral dynamics and the time to decrease in CD4/CD8 ratio in the presence of CD4 counts with measurement errors to compare potential models with various scenarios and different distribution specifications. The analysis outcome indicates that the time-varying CD4 covariate is closely related to the first-phase viral decay rate, but the time to CD4/CD8 decrease is not highly associated with either the two viral decay rates or the CD4 changing rate over time. These findings may provide some quantitative guidance to better understand the relationship of the virological and immunological responses to antiretroviral treatments.  相似文献   
329.
Starting from two known continuous univariate distributions, a bivariate distribution is constructed depending on a parameter which measures the degree of stochastic dependence between the two random variables. From the foregoing construction we then pass to a multivariate-type distribution, constructed using only univariate distributions and an association matrix. Some properties of the multivariate and bivariate case are studied.  相似文献   
330.
In this paper, we investigate how government transparency depends on economic distortions. We first consider an abstract class of economies in which a benevolent policy maker is privately informed about the exogenous state of the economy and contemplates whether to release this information. Our key result is that distortions limit communication: even if transparency is ex ante Pareto superior to opaqueness, it cannot constitute an equilibrium when distortions are sufficiently high. We next confirm this broad insight in two applied contexts, in which monopoly power and income taxes are the specific sources of distortions.  相似文献   
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