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   191篇
  免费   12篇
管理学   29篇
人口学   13篇
丛书文集   1篇
理论方法论   28篇
综合类   1篇
社会学   72篇
统计学   59篇
  2024年   2篇
  2023年   5篇
  2022年   1篇
  2021年   3篇
  2020年   4篇
  2019年   17篇
  2018年   16篇
  2017年   16篇
  2016年   11篇
  2015年   11篇
  2014年   10篇
  2013年   27篇
  2012年   7篇
  2011年   11篇
  2010年   7篇
  2009年   7篇
  2008年   4篇
  2007年   4篇
  2006年   4篇
  2005年   3篇
  2004年   6篇
  2003年   10篇
  2002年   2篇
  2001年   4篇
  1997年   1篇
  1996年   2篇
  1995年   1篇
  1994年   2篇
  1993年   1篇
  1991年   2篇
  1985年   1篇
  1984年   1篇
排序方式: 共有203条查询结果,搜索用时 15 毫秒
1.
A Markov chain Monte Carlo (MCMC) approach, called a reversible jump MCMC, is employed in model selection and parameter estimation for possibly non-stationary and non-linear time series data. The non-linear structure is modelled by the asymmetric momentum threshold autoregressive process (MTAR) of Enders & Granger (1998) or by the asymmetric self-exciting threshold autoregressive process (SETAR) of Tong (1990). The non-stationary and non-linear feature is represented by the MTAR (or SETAR) model in which one ( 𝜌 1 ) of the AR coefficients is greater than one, and the other ( 𝜌 2 ) is smaller than one. The other non-stationary and linear, stationary and nonlinear, and stationary and linear features, represented respectively by ( 𝜌 1 = 𝜌 2 = 1 ), ( 𝜌 1 p 𝜌 2 < 1 ) and ( 𝜌 1 = 𝜌 2 < 1 ), are also considered as possible models. The reversible jump MCMC provides estimates of posterior probabilities for these four different models as well as estimates of the AR coefficients 𝜌 1 and 𝜌 2 . The proposed method is illustrated by analysing six series of US interest rates in terms of model selection, parameter estimation, and forecasting.  相似文献   
2.
Summary.  The paper considers the problem of estimating the entire temperature field for every location on the globe from scattered surface air temperatures observed by a network of weather-stations. Classical methods such as spherical harmonics and spherical smoothing splines are not efficient in representing data that have inherent multiscale structures. The paper presents an estimation method that can adapt to the multiscale characteristics of the data. The method is based on a spherical wavelet approach that has recently been developed for a multiscale representation and analysis of scattered data. Spatially adaptive estimators are obtained by coupling the spherical wavelets with different thresholding (selective reconstruction) techniques. These estimators are compared for their spatial adaptability and extrapolation performance by using the surface air temperature data.  相似文献   
3.
This study is to empirically testify that corporate elitism is an antecedent to groupthink, which prevents organizational empathy from working effectively in crises. The current study is expected to expand the boundary of crisis management literature into a company’s crisis-preparedness before a crisis occurs. The findings offer the useful guidance to organizations on how to better manage their crisis proneness through identifying the early signs of corporate elitism and groupthink.  相似文献   
4.
This article proposes a linearly weighted unit root test with a new weighting scheme which reflects the trade-off in power between the ADF and LM tests regarding the initial value of a time series. Simulation results indicate that the proposed test has better power performance and works better than other available tests in the literature for a range of initial conditions.  相似文献   
5.
Objective: Despite declining cigarette smoking rates in the US, there is a continued need for tobacco prevention education campaigns to reach young adults. Recognizing the need for improved tobacco control messaging, the University of Texas (UT) System engaged The University of Texas at Austin Center for Health Communication to develop a brand and message that would strengthen tobacco control efforts at its 14 institutions. Methods: This article describes the iterative process involved in creating a brand for tobacco control, including an environmental scan, identifying potential message themes, and creating and refining logos. Results: This article highlights the process of developing a system-wide tobacco control brand. Specifically, the process included coordinating an interdisciplinary team with content and design experts, and presenting ideas to stakeholders for serial feedback and refinement, among others. Conclusions: Ultimately, this project offers a model for other systems of higher education interested in pursuing similar initiatives.  相似文献   
6.
Robust parameter designs (RPDs) enable the experimenter to discover how to modify the design of the product to minimize the effect due to variation from noise sources. The aim of this article is to show how this amount of work can be reduced under modified central composite design (MCCD). We propose a measure of extended scaled prediction variance (ESPV) for evaluation of RPDs on MCCD. Using these measures, we show that we can check the error or bias associated with estimating the model parameters and suggest the values of α recommended for MCCS under minimum ESPV.  相似文献   
7.
This study extends Flores et al.'s ( 2006 ) 36‐year analysis of racial/ethnic minority (REM) career research to identify recent trends in choice of topics and leading individual and institutional contributors. The authors identified 166 articles on REM career research published from 2005 to 2015 in the Journal of Vocational Behavior, The Career Development Quarterly, the Journal of Career Assessment, and the Journal of Career Development. Of these studies, 92% were empirical, with more than three quarters of these using quantitative rather than qualitative methodology. Most frequently, the empirical studies (n = 153) were based on samples of high school (30.7%) or undergraduate (34.6%) students. The authors discuss the implications of their findings and suggest ways to expand REM career research in the future.  相似文献   
8.
本文使用19982008年的韩国劳动面板调查数据,将期望薪资作为保留薪资的代理变量纳入Logit模型,分析韩国青年求职者期望薪资与潜在薪资之间的差异(即高眼光因素)对青年就业的影响。分析结果表明,青年男性求职者期望薪资越高于潜在市场薪资,就业概率越低。但这一结果不适用于中年求职者与女性求职者的就业问题。此外,年龄、学历、求职途径、求职地区、婚姻状态等也对青年就业产生影响。  相似文献   
9.
Structural breaks in the level as well as in the volatility have often been exhibited in economic time series. In this paper, we propose new unit root tests when a time series has multiple shifts in its level and the corresponding volatility. The proposed tests are Lagrangian multiplier type tests based on the residual's marginal likelihood which is free from the nuisance mean parameters. The limiting null distributions of the proposed tests are the χ2distributions, and are affected not by the size and the location of breaks but only by the number of breaks.

We set the structural breaks under both the null and the alternative hypotheses to relieve a possible vagueness in interpreting test results in empirical work. The null hypothesis implies a unit root process with level shifts and the alternative connotes a stationary process with level shifts. The Monte Carlo simulation shows that our tests are locally more powerful than the OLSE-based tests, and that the powers of our tests, in a fixed time span, remain stable regardless the number of breaks. In our application, we employ the data which are analyzed by Perron (1990), and some results differ from those of Perron's (1990).  相似文献   

10.
The challenge for policy makers and disaster managers is to achieve a balance between two dynamics — resilience and entropy — in order to develop sustainable risk reduction. Achieving an appropriate balance between resilience and entropy in any given community requires a systematic exploration of both dynamics. The recent hurricanes that struck Louisiana, Hurricane Katrina on August 29, 2005 and Hurricane Gustav, on September 1, 2008, offer an unusual opportunity to assess the degree to which both dynamics operated following Hurricane Katrina.  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