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81.
The declining capacities in older people often lead to limitations in activities of daily living and a simultaneous rising demand for care services. Many of these limitations in daily activities are to a varying degree caused, enhanced or facilitated by disadvantageous housing and environmental conditions. Home modifications have been credited as an important part of the solution, allowing for an extended and safer use of the home. In order to examine this issue in more detail, this paper provides empirical evidence on the type and extent of risks associated with accidents around the home. It reports on findings from a European case study on the difficulties using the home and risks of accidents which may lead to injury. It is argued that healthy housing conditions for older persons are important to maximize the supportive capacity of one's home, to stimulate an active and healthy lifestyle, and to avoid unnecessary institutionalization. 相似文献
82.
This study investigated the executive influence of public relations managers in the German higher education system. The study is based on a whole-population survey of German university decision makers (N = 1619). It provides evidence that the mediatization of German higher education offers an important opportunity for the empowerment of university PR departments. They can benefit from the New Public Management reforms in recent years as power shifts to management-oriented administrators and the public image of universities turns into a competitive asset. Nevertheless, an indispensable precondition for PR departments’ organizational advancement resides in professionalization. PR workers need to claim a status of expert boundary spanners between their universities and the public stakeholders. 相似文献
83.
Review of Economics of the Household - There is substantial evidence that due to perceived childcare obligations, mothers are disadvantaged in labor markets. To what extent can childcare support... 相似文献
84.
Andrew M. Raim Matthias K. Gobbert Nagaraj K. Neerchal Jorge G. Morel 《Journal of Statistical Computation and Simulation》2013,83(12):2178-2194
Numerical methods are needed to obtain maximum-likelihood estimates (MLEs) in many problems. Computation time can be an issue for some likelihoods even with modern computing power. We consider one such problem where the assumed model is a random-clumped multinomial distribution. We compute MLEs for this model in parallel using the Toolkit for Advanced Optimization software library. The computations are performed on a distributed-memory cluster with low latency interconnect. We demonstrate that for larger problems, scaling the number of processes improves wall clock time significantly. An illustrative example shows how parallel MLE computation can be useful in a large data analysis. Our experience with a direct numerical approach indicates that more substantial gains may be obtained by making use of the specific structure of the random-clumped model. 相似文献
85.
Gregory Connor Matthias Hagmann Oliver Linton 《Econometrica : journal of the Econometric Society》2012,80(2):713-754
This paper develops a new estimation procedure for characteristic‐based factor models of stock returns. We treat the factor model as a weighted additive nonparametric regression model, with the factor returns serving as time‐varying weights and a set of univariate nonparametric functions relating security characteristic to the associated factor betas. We use a time‐series and cross‐sectional pooled weighted additive nonparametric regression methodology to simultaneously estimate the factor returns and characteristic‐beta functions. By avoiding the curse of dimensionality, our methodology allows for a larger number of factors than existing semiparametric methods. We apply the technique to the three‐factor Fama–French model, Carhart's four‐factor extension of it that adds a momentum factor, and a five‐factor extension that adds an own‐volatility factor. We find that momentum and own‐volatility factors are at least as important, if not more important, than size and value in explaining equity return comovements. We test the multifactor beta pricing theory against a general alternative using a new nonparametric test. 相似文献
86.
Online (also ‘real-time’ or ‘sequential’) signal extraction from noisy and outlier-interfered data streams is a basic but challenging goal. Fitting a robust Repeated Median (Siegel in Biometrika 69:242–244, 1982) regression line in a moving time window has turned out to be a promising approach (Davies et al. in J. Stat. Plan. Inference 122:65–78, 2004; Gather et al. in Comput. Stat. 21:33–51, 2006; Schettlinger et al. in Biomed. Eng. 51:49–56, 2006). The level of the regression line at the rightmost window position, which equates to the current time point in an online application, is then used for signal extraction. However, the choice of the window width has a large impact on the signal extraction, and it is impossible to predetermine an optimal fixed window width for data streams which exhibit signal changes like level shifts and sudden trend changes. We therefore propose a robust test procedure for the online detection of such signal changes. An algorithm including the test allows for online window width adaption, meaning that the window width is chosen w.r.t. the current data situation at each time point. Comparison studies show that our new procedure outperforms an existing Repeated Median filter with automatic window width selection (Schettlinger et al. in Int. J. Adapt. Control Signal Process. 24:346–362, 2010). 相似文献
87.
We propose a new regression-based filter for extracting signals online from multivariate high frequency time series. It separates relevant signals of several variables from noise and (multivariate) outliers. Unlike parallel univariate filters, the new procedure takes into account the local covariance structure between the single time series components. It is based on high-breakdown estimates, which makes it robust against (patches of) outliers in one or several of the components as well as against outliers with respect to the multivariate covariance structure. Moreover, the trade-off problem between bias and variance for the optimal choice of the window width is approached by choosing the size of the window adaptively, depending on the current data situation. Furthermore, we present an advanced algorithm of our filtering procedure that includes the replacement of missing observations in real time. Thus, the new procedure can be applied in online-monitoring practice. Applications to physiological time series from intensive care show the practical effect of the proposed filtering technique. 相似文献
88.
The personalities of central bankers moved center stage during the recent financial crisis. Indeed, several central bankers even became “superstars.” In this article, we investigate whether superstar central bankers have an impact on economic performance. We employ school grades given to central bankers by the financial press, defining as superstars those central bankers receiving the top grade. First, we explain the grades in a probit estimation with measures of economic performance, institutional features, and personal characteristics. Second, we employ a matching approach to account for the endogeneity of grading with respect to economic performance. Using entropy balancing, we identify credible counterfactuals for top‐graded central bankers, that is, nonsuperstar central bankers who face similar situations. Comparing the economic performance of both groups, we find that superstars do indeed matter: a top‐graded central banker faces a significantly more favorable output‐inflation tradeoff than his peers. This effect is driven by outstanding central bankers in both advanced and emerging economies and is especially prevalent in the precrisis subsample. (JEL E52, E58) 相似文献
89.
This contribution is written against the backdrop of the historic dispersal of early American media sociology out from the core concerns of the discipline and into various importer academic disciplines (including communication, journalism, and media studies) and an ever‐growing pervasiveness of media in everyday life which is reflected by a resurgence of sociological scholarship in the United States since the early 2000s. The article divides the field in works that study media inwards – along the threefold dimensions of production and technologies, communication and discourse, reception and effects – and works that study media outwards. We argue that this latter perspective, examining broader theoretical, methodological, and substantive social implications of mass‐mediated communication, is the most promising one for a mature field of American media sociology. On this basis, we conclude with some suggestions regarding possible new, and as of yet understudied, lines of inquiry for future media sociologists. 相似文献
90.
Matthias Menter Erik E. Lehmann Torben Klarl 《Zeitschrift für Betriebswirtschaft》2018,88(9):1105-1132
As higher education policies are often associated with intense public spending, the evaluation and performance measurement of respective initiatives becomes increasingly crucial. An extensive and fruitful strand of literature has dealt with the assessment of university performance, yet mainly focused on point-in-time rather than period-of-time examinations. This study investigates the effects of Germany’s first Excellence Initiative, a political measure aimed at building up world-class universities to be able to compete in the globalizing research world. Relying on both qualitative and quantitative measures, taking into account a 15-year period from 1998 to 2012, we analyze the selection process and how and whether the Excellence Initiative fulfilled its ambitious goals. Our results suggest that not the political initiative per se, i.e. the treatment, but the announcement of the treatment triggered diverging performance paths within the German higher education system, thus positively contributed to augmented research performance of the promoted universities. Based on these findings, we provide policy recommendations and avenues for future research. 相似文献