首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   1718篇
  免费   67篇
  国内免费   20篇
管理学   79篇
民族学   10篇
人口学   14篇
丛书文集   161篇
理论方法论   65篇
综合类   1140篇
社会学   71篇
统计学   265篇
  2024年   2篇
  2023年   16篇
  2022年   14篇
  2021年   16篇
  2020年   25篇
  2019年   32篇
  2018年   43篇
  2017年   38篇
  2016年   50篇
  2015年   57篇
  2014年   112篇
  2013年   148篇
  2012年   127篇
  2011年   140篇
  2010年   115篇
  2009年   120篇
  2008年   120篇
  2007年   109篇
  2006年   115篇
  2005年   87篇
  2004年   78篇
  2003年   60篇
  2002年   52篇
  2001年   30篇
  2000年   27篇
  1999年   12篇
  1998年   7篇
  1997年   9篇
  1996年   10篇
  1995年   5篇
  1994年   6篇
  1993年   5篇
  1992年   5篇
  1991年   3篇
  1990年   1篇
  1988年   3篇
  1987年   1篇
  1986年   2篇
  1983年   1篇
  1982年   1篇
  1979年   1篇
排序方式: 共有1805条查询结果,搜索用时 15 毫秒
91.
We propose an adaptive functional autoregressive (AFAR) forecast model to predict electricity price curves. With time-varying operators, the AFAR model can be safely used in both stationary and nonstationary situations. A closed-form maximum likelihood (ML) estimator is derived under stationarity. The result is further extended for nonstationarity, where the time-dependent operators are adaptively estimated under local homogeneity. We provide theoretical results of the ML estimator and the adaptive estimator. Simulation study illustrates nice finite sample performance of the AFAR modeling. The AFAR model also exhibits a superior accuracy in the forecast exercise of the California electricity daily price curves compared to several alternatives.  相似文献   
92.
The paper investigates various nonparametric models including regression, conditional distribution, conditional density and conditional hazard function, when the covariates are infinite dimensional. The main contribution is to prove uniform in bandwidth asymptotic results for kernel estimators of these functional operators. Then, the application issues, involving data-driven bandwidth selection, are discussed.  相似文献   
93.
High-content automated imaging platforms allow the multiplexing of several targets simultaneously to generate multi-parametric single-cell data sets over extended periods of time. Typically, standard simple measures such as mean value of all cells at every time point are calculated to summarize the temporal process, resulting in loss of time dynamics of the single cells. Multiple experiments are performed but observation time points are not necessarily identical, leading to difficulties when integrating summary measures from different experiments. We used functional data analysis to analyze continuous curve data, where the temporal process of a response variable for each single cell can be described using a smooth curve. This allows analyses to be performed on continuous functions, rather than on original discrete data points. Functional regression models were applied to determine common temporal characteristics of a set of single cell curves and random effects were employed in the models to explain variation between experiments. The aim of the multiplexing approach is to simultaneously analyze the effect of a large number of compounds in comparison to control to discriminate between their mode of action. Functional principal component analysis based on T-statistic curves for pairwise comparison to control was used to study time-dependent compound effects.  相似文献   
94.
More flexible semiparametric linear‐index regression models are proposed to describe the conditional distribution. Such a model formulation captures varying effects of covariates over the support of a response variable in distribution, offers an alternative perspective on dimension reduction and covers a lot of widely used parametric and semiparameteric regression models. A feasible pseudo likelihood approach, accompanied with a simple and easily implemented algorithm, is further developed for the mixed case with both varying and invariant coefficients. By justifying some theoretical properties on Banach spaces, the uniform consistency and asymptotic Gaussian process of the proposed estimator are also established in this article. In addition, under the monotonicity of distribution in linear‐index, we develop an alternative approach based on maximizing a varying accuracy measure. By virtue of the asymptotic recursion relation for the estimators, some of the achievements in this direction include showing the convergence of the iterative computation procedure and establishing the large sample properties of the resulting estimator. It is noticeable that our theoretical framework is very helpful in constructing confidence bands for the parameters of interest and tests for the hypotheses of various qualitative structures in distribution. Generally, the developed estimation and inference procedures perform quite satisfactorily in the conducted simulations and are demonstrated to be useful in reanalysing data from the Boston house price study and the World Values Survey.  相似文献   
95.
This paper studies M-estimation in functional linear regression in which the dependent variable is scalar while the covariate is a function. An estimator for the slope function is obtained based on the functional principal component basis. The global convergence rate of the M-estimator of unknown slope function is established. The convergence rate of the mean-squared prediction error for the proposed estimators is also established. Monte Carlo simulation studies are conducted to examine the finite-sample performance of the proposed procedure. Finally, the proposed method is applied to analyze the Berkeley growth data.  相似文献   
96.
《决策科学》2017,48(1):39-70
Manufacturing process improvement teams often draw upon cross‐functional expertise. However, teams dominated by a single or few functions often do not achieve the desired interdisciplinary learning and cooperation, which in turn could negatively affect the performance of that cross‐functional team. Through an empirical analysis of 149 manufacturing process improvement teams in six SIC industrial categories, we show that even after controlling for several factors such as team size, number of functions, gender diversity, ethnicity, number of management levels, and geographic dispersion of team members, psychological safety of work environment fully mediates the relationship between functional dominance and team performance. We also confirm that a team leader possessing high interpersonal justice mitigates the deficiency of dominated teams and improves team performance by fostering a psychologically safe work environment. Our recommendation therefore is that when a dominated team is unavoidable due to the needed skill sets or other organizational considerations, to ensure success it is imperative that the firm chooses a team leader who can promote psychological safety by being just, and who can effectively encourage input from all functional team members and give them objective feedback.  相似文献   
97.
The purpose of this article is to recover Williams as a major theoretical inspiration for the social sciences, specifically, as the inaugurator of what might be regarded as a research paradigm, cultural materialism. In the first section, Williams's encounter with the discipline of sociology is traced and distinguished as a critical alternative to the presently ascendant – at least in the USA – neo‐Durkeimian school of ‘cultural sociology’. In the second section, his cultural‐materialist programme is proposed as a powerful analytical framework for the study of culture and society today. In the final section, a key concept of Williams's cultural materialism, mobile privatization, is selected illustratively and proposed as a powerful analytical tool for studying the production and technological mediation of typical modes of communicative sociality in the early twenty‐first century.  相似文献   
98.
The aims of this article are threefold: One, to focus on the advertising and marketing communications situating the presence of the USA in India. Two, to address three issues concerning the where, how, and impact dimensions of marking the US presence in Indian advertising. In that process an attempt will be made to integrate three aspects of advertising, namely: marketing, media, and linguistics. Three, to account for US corporate culture as it manifests itself in advertising. Central to our discussion are two product types: consumer products (e.g. Coke, Pepsi, Kellogg’s cereals, or Cadbury’s chocolates) and socially-sensitive, or ‘taboo’, products (e.g. condoms, alcohol, and breath fresheners).  相似文献   
99.
朱政惠 《学术月刊》2012,(1):131-135
乔治忠认为,中国史学史学科体系的建设具有不同的构成层次,界定其学术任务和研究内容,展现学科性质的板块式逻辑结构,明晰学术研究的切入点,是独立学科地位能够成立的基础;探研中国传统史学发展的主导线索,划分中国史学的发展阶段,是在深入研究条件下的整体性把握。罗炳良认为,中国史学史的学科体系渐臻成熟,中国史学史研究也应当拓宽学术领域,促进史学史的内涵和体系不断深入和完善;要实现这个目标,至关重要的是加强史学思潮和史学批评范畴两个领域的研究。钱茂伟认为,需要用新的视角来研究史学史,一是用史学范型观照传统史学的发展历程,二是用国家与社会关系视角观照史学的发展历程;特别要重视研究民间史学,注重小历史的书写研究。朱政惠认为,中国史学史研究要放到国际中国史学史、东西方史学研究和交流的大环境中考察,从历史的纵向考察和横向的比较中探寻中国史学史研究的新方向。  相似文献   
100.
通过对电子商务法功能等同原则基本内涵的剖析以及国际国内电子商务法对功能等同原则的体现,阐述了为什么只有电子商务法领域才有功能等同原则、功能等同原则是如何与其它原则一同构成电子商务法基本原则体系的、功能等同原则对立法和司法实践具有什么指导意义,并最终得出功能等同原则不应该长久地作为电子商务法的基本原则的结论。  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号