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41.
E-petitioning platforms are increasingly popular in Western democracies and considered by some lawmakers and scholars to enhance citizen participation in political decision-making. In addition to social media and other channels for informal political communication, online petitioning is regarded as both a useful instrument to afford citizens a more important role in the political process and allow them to express support for issues which they find relevant. Building on existing pre-internet systems, e-petitioning websites are increasingly implemented to make it easier and faster to set up and sign petitions. However, little attention has so far been given to the relationship between different styles of usage and the causes supported by different groups of users. The functional difference between signing paper-based petitions vs. doing so online is especially notable with regard to users who sign large numbers of petitions. To characterize this relationship, we examine the intensity of user participation in the German Bundestag’s online petitioning platform through the lens of platform data collected over a period of five years, and conduct an analysis of highly active users and their political preferences. We find that users who sign just a single petition favor different policy areas than those who sign many petitions on a variety of issues. We conclude our analysis with observations on the potential of behavioral data for assessing the dynamics of online participation, and suggest that quantity (the number of signed petitions) and quality (favored policy areas) need more systematic joint assessment.  相似文献   
42.
In general, the exact distribution of a convolution of independent gamma random variables is quite complicated and does not admit a closed form. Of all the distributions proposed, the gamma-series representation of Moschopoulos (1985 Moschopoulos, P. G. (1985). The distribution of the sum of independent gamma random variables. Annals of the Institute of Statistical Mathematics 37Part A:541544. [Google Scholar]) is relatively simple to implement but for particular combinations of scale and/or shape parameters the computation of the weights of the series can result in complications with too much time consuming to allow a large-scale application. Recently, a compact random parameter representation of the convolution has been proposed by Vellaisamy and Upadhye (2009 Vellaisamy, P., Upadhye, N. S. (2009). On the sums of compound negative binomial and gamma random variables. Journal of Applied Probability 46:272283.[Crossref], [Web of Science ®] [Google Scholar]) and it allows to give an exact interpretation to the weights of the series. They describe an infinite discrete probability distribution. This result suggested to approximate Moschopoulos’s expression looking for an approximating theoretical discrete distribution for the weights of the series. More precisely, we propose a general negative binomial distribution. The result is an “excellent” approximation, fast and simple to implement for any parameter combination.  相似文献   
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To improve the quality of prediction of radioactive contamination, geostatistical methods, and in particular multivariate geostatistical models, are increasingly being used. These methods, however, are optimal only in the case in which the data may be assumed Gaussian and do not properly cope with data measurements that are discrete, nonnegative or show some degree of skewness. To deal with these situations, here we consider a hierarchical model in which non-Gaussian variables of different kind are handled simultaneously. We show that when observations are assumed to be conditionally distributed as Poisson and Gamma, variograms and cross-variograms have convenient simple forms, and estimation of the parameters of the model can be carried out by Monte Carlo EM. This work was inspired by radioactive contamination data from the Maddalena Archipelago (Sardinia, Italy).  相似文献   
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Our study aims to assess the prevalence of behavioural addictions in an adolescent population, evaluating the effects of gender and age, and to assess the correlations among different behavioural addictions. 2853 high school students were assessed in order to evaluate the prevalence of behavioural addictions such as Pathological Gambling (PG), Compulsive Buying (CB), Exercise Addiction (EA), Internet Addiction (IA), and Work Addiction (WA), in a population of Italian adolescents. The South Oaks Gambling Screen-Revised Adolescent (SOGS-RA), the Compulsive Buying Scale (CBS), the Exercise Addiction Inventory (EAI), the Internet Addiction Test (IAT), and the Work Addiction Risk Test (WART), were compiled anonymously by the students. Overall prevalence was 7.0% for PG, 11.3% for CB, 1.2% for IA, 7.6% for WA, 8.5% for EA. PG and EA were more common among boys, while gender had no effect on the other conditions. CB was more common among younger (<18 years old) students. The scores of all of these scales were significantly correlated. The strong correlation among different addictive behaviours is in line with the hypothesis of a common psychopathological dimension underlying these phenomena. Further studies are needed to assess personality traits and other clinical disorders associated with these problems behaviours.  相似文献   
47.
Cohabitation in Great Britain: not for long, but here to stay   总被引:2,自引:1,他引:1  
This paper uses a new source of data to study the dramatic increase in cohabiting unions in Great Britain. It analyses, in turn, entry into first partnership, the stability of cohabiting unions and repartnering after dissolution of cohabitation. In excess of 70% of first partnerships are now cohabitations, and these last a relatively short time before being either turned into marriage or dissolved. The shift to cohabitation as the dominant mode of first partnership plays an important role in the delay of first marriage and motherhood. The paper also investigates the factors that are associated with the outcome of cohabitations.  相似文献   
48.
There is a need for culturally attuned approaches for couple therapy with Mexican/Mexican‐Americans. This qualitative grounded theory study utilized interviews with 11 client couples of Mexican heritage and 14 marital and family therapists to shed light on how Latino and non‐Latino therapists co‐construct positive experiences of cultural attunement with Mexican and Mexican‐American couple clients. Analysis identified a model of cultural connection through personal engagement with four interrelated phases: (a) mutual invitation, (b) shared engagement, (c) expanding personal connection, and (d) creating cultural connections. Clients in this study valued professionalism and expertise of the therapist, but felt attuned to and respected when therapists demonstrated humility, shared personal stories and emotion, and engaged in a collaborative process.  相似文献   
49.
The present research investigated whether enhanced perceptions of moral purity drive the effects of intergroup cross-group friendships on the intentions to interact with homosexuals. High-school students (= 639) reported their direct and extended cross-group friendships with homosexuals as well as their beliefs regarding the moral character of the sexual minority. Participants further reported their desire to interact with homosexuals in the future. Results showed that both face-to-face encounters and extended contact with homosexuals increased their perceived moral purity, which in turn fostered more positive behavioral intentions. Results further revealed the specific role of moral purity in this sense, as differential perceptions along other moral domains (autonomy and community) had no mediation effects on behavioral tendencies toward homosexuals. The importance of these findings for improving intergroup relations is discussed, together with the importance of integrating research on intergroup contact and morality.  相似文献   
50.
The two experimental methods most commonly used for reducing the effect of noise factors on a response of interest Y aim either to estimate a model of the variability (V(Y), or an associated function), that is transmitted by the noise factors, or to estimate a model of the ratio between the response (Y) and all the control and noise factors involved therein. Both methods aim to determine which control factor conditions minimise the noise factors' effect on the response of interest, and a series of analytical guidelines are established to reach this end. Product array designs allow robustness problems to be solved in both ways, but require a large number of experiments. Thus, practitioners tend to choose more economical designs that only allow them to model the surface response for Y. The general assumption is that both methods would lead to similar conclusions. In this article we present a case that utilises a design based on a product design and for which the conclusions yielded by the two analytical methods are quite different. This example casts doubt on the guidelines that experimental practice follows when using either of the two methods. Based on this example, we show the causes behind these discrepancies and we propose a number of guidelines to help researchers in the design and interpretation of robustness problems when using either of the two methods.  相似文献   
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