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161.
In this paper we consider the Capital Asset Pricing Model under Elliptical (symmetric) Distributions. This class of distributions, which contains the normal distribution, t, contaminated normal and power exponential, among others, offers a more flexible framework for modelling asset prices or returns. In order to analyze the sensibility to possible outliers and/or atypical returns of the maximum likelihood estimators, the local influence method was implemented. The results are illustrated by using a set of shares from companies who trade in the Chilean Stock Market. Our main conclusion is that symmetric distributions having heavier tails than those of the normal distribution, especially the t distribution with small degrees of freedom, show a better fit and allow the reduction of the influence of atypical returns in the maximum likelihood estimators.  相似文献   
162.
During the last few years, changes in the Spanish educational system have had a far reaching impact. Several factors have been critical: (1) the progressive decentralization of education by the government, now a responsibility of regional governments; (2) the extension of compulsory education to the age of 16; and finally (3) the increase in the number of immigrant students, which has significantly added to the existing cultural diversity. The enrolment of immigrant students in Spanish schools is a relatively recent phenomenon (starting 15 years ago) when compared with other European countries. Madrid is the region in Spain with the largest number of students. As most of these students were born outside of Spain, we cannot yet speak of a second generation. The research described here investigated how the educational system in Madrid confronted the challenge of an increasing number of immigrant students. The institutional response was the Madrid Regional Government’s Compensatory Education Regional Plan. This encompasses several measures, which are described here. After a critical analysis of educational policies pertaining to immigrant pupils, the paper suggests ways of overcoming a purely compensatory approach. Intercultural education plays a key role is such considerations.  相似文献   
163.
This article presents theoretical elements concerning the ‘nature versus culture’ confrontation as a particular aspect of the worldwide expansion of Western civilization. Several speculations are made concerning the philosophical foundations which have provided the base for the current political and economic mega-scenarios in the contemporary world. We turn our attention to the articulations of the concept of nature with the processes of mondialization of Western culture and with the history of universal culture. Finally, several considerations are made on the dynamics of economic processes on a world scale and projections on the impact of science and technology in the social and political frames that are taking place in the contemporary world.  相似文献   
164.
Firms mitigate uncertainty in demand and supply by carrying safety stock, planning for excess capacity and diversifying supply sources. In this study, we provide a framework to jointly optimize these three levers in a periodic review infinite horizon setting, and in particular we examine how one can reduce inventory and capacity investments through proper diversification strategies. Observing that a modified base‐stock inventory policy is optimal, we find that the capacity‐diversification problem is well behaved and characterize the optimal mix of safety stock, excess capacity and extra number of supply sources. We find that higher supply uncertainty results in higher safety stock, more excess capacity, and higher diversification. But safety stock and diversification are non‐monotonic in demand uncertainty. Our results can be extended to situations in which suppliers are heterogeneous, and can be used to develop effective heuristics.  相似文献   
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The immigrant paradox is a population health pattern whereby later generation immigrant youth display less favorable outcomes when compared to first‐generation co‐ethnic peers. This study examines the role of number of sex partners in explaining the immigrant paradox in pregnancy among Latina adolescents. This secondary analysis utilized a nationally representative sample of Latinas in the National Longitudinal Study of Adolescent Health. As expected, first‐generation Latina adolescents demonstrated less risk than second‐ or third+ generation Latinas for becoming pregnant. Further, the lower number of sexual partners fully accounted for the first generation's advantage in lower rate of adolescent pregnancy. These findings have important implications for healthcare providers who work with Latina girls in pregnancy prevention.  相似文献   
169.
In this article we unify the traditional approaches to testing for fiscal sustainability considering the stock‐flow system that fiscal variables configure. Our approach encompasses previous ways of testing for sustainability. The results obtained for a group of 17 Organization for Economic Cooperation and Development (OECD) countries point to weak fiscal sustainability, as well as to the existence of cointegration between deficit and debt, confirming the relevance of the stock‐flow approach. Allowing for structural breaks and multicointegration turns out to be of critical importance to assess whether the fiscal authorities apply their policies looking for sustainability and whether, simultaneously, they try to stabilize real debt target levels. (JEL H62, E62, C22)  相似文献   
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ABSTRACT

The practice of public relations in Spain began during the Franco dictatorship, which was established in 1939, following a 3-year civil war. The first consultancy was opened in Barcelona in 1960, at the beginning of a period of economic growth due to a change of direction in the regime. After the end of the autarchy and international ostracism, Spain began an unprecedented economic and social transformation. Public relations thus helped businesses to make contact with an ever-better-informed media and public opinion and, in this way, contributed to economic development while simultaneously promoting associationism and improvement in the teaching of the subject.  相似文献   
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