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   651篇
  免费   53篇
  国内免费   42篇
  2024年   3篇
  2023年   26篇
  2022年   26篇
  2021年   28篇
  2020年   45篇
  2019年   41篇
  2018年   33篇
  2017年   39篇
  2016年   42篇
  2015年   14篇
  2014年   24篇
  2013年   59篇
  2012年   11篇
  2011年   12篇
  2010年   8篇
  2009年   17篇
  2008年   16篇
  2007年   20篇
  2006年   21篇
  2005年   21篇
  2004年   16篇
  2003年   12篇
  2002年   19篇
  2001年   9篇
  2000年   11篇
  1999年   6篇
  1998年   8篇
  1997年   6篇
  1996年   6篇
  1995年   16篇
  1994年   3篇
  1993年   8篇
  1992年   6篇
  1991年   7篇
  1990年   6篇
  1989年   12篇
  1988年   9篇
  1987年   5篇
  1986年   5篇
  1985年   4篇
  1984年   3篇
  1983年   6篇
  1982年   6篇
  1981年   3篇
  1980年   4篇
  1979年   15篇
  1978年   9篇
  1977年   8篇
  1976年   7篇
  1974年   2篇
排序方式: 共有746条查询结果,搜索用时 15 毫秒
51.
We used the take‐the‐best heuristic to develop a model to forecast the popular two‐party vote shares in U.S. presidential elections. The model draws upon information about how voters expect the candidates to deal with the most important issue facing the country. We used cross‐validation to calculate a total of 1000 out‐of‐sample forecasts, one for each of the last 100 days of the ten U.S. presidential elections from 1972 to 2008. Ninety‐seven per cent of forecasts correctly predicted the winner of the popular vote. The model forecasts were competitive compared to forecasts from methods that incorporate substantially more information (e.g., econometric models and the Iowa Electronic Markets). The purpose of the model is to provide fast advice on which issues candidates should stress in their campaign. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   
52.
The commentary discusses several topics in Dr. Iacobucci's article on mediation analysis with categorical variables including the lack of equivalency of mediated effect measures, ab, and cc′, that are algebraically equivalent in ordinary least squares regression models. The commentary raises the issue of correlated mediation coefficients and presents formulas to include the correlation in the test of significance. References to new developments in causal mediation analysis for categorical variables are given and the importance of programs of research to establish a mediation theory is emphasized.  相似文献   
53.
This paper provides an overview and task analysis for creating a continuous ABC data‐collection application using Xcode on a Mac computer. Behavior analysts can program an ABC data collection system, complete with a customized list of target clients, antecedents, behaviors, and consequences to be recorded, and have the data automatically sent to an e‐mail account after observations have concluded. Further suggestions are provided to customize the ABC data‐ collection system for individual preferences and clinical needs.  相似文献   
54.
Presently, the collection and analysis of naturalistic data is the most credited method for understanding road user behavior and improving traffic safety. Such methodology was developed for motorized vehicles, such as cars and trucks, and is still largely applied to those vehicles. However, a reasonable question is whether bicycle safety can also benefit from the naturalistic methodology, once collection and analyses are properly ported from motorized vehicles to bicycles. This paper answers this question by showing that instrumented bicycles can also collect analogous naturalistic data. In addition, this paper shows how naturalistic cycling data from 16 bicyclists can be used to estimate risk while cycling. The results show that cycling near an intersection increased the risk of experiencing a critical event by four times, and by twelve times when the intersection presented some form of visual occlusion (e.g., buildings and hedges). Poor maintenance of the road increased the risk tenfold. Furthermore, the risk of experiencing a critical event was twice as large when at least one pedestrian or another bicyclist crossed the bicyclist’s trajectory. Finally, this study suggests the two most common scenarios for bicycle accidents, which result from different situations and thus require different countermeasures. The findings presented in this paper show that bicycle safety can benefit from the naturalistic methodology, which provides data able to guide development and evaluation of (intelligent) countermeasures to increase cycling safety.  相似文献   
55.
A large body of research has investigated the psycho-organizational variables predicting satisfaction at work, but few studies have so far examined variables in the field of environmental psychology. Our study aims first to identify the impact of variables evaluating comfort at work (satisfaction with the work environment, attachment to the workplace) by comparing them with organizational variables known to be related to job satisfaction, and then to rank the relationships between these variables in a pseudo- implication sequence, based on statistical implicative analysis. The study involved 105 bank employees and confirms our theoretical model, showing that job satisfaction can be explained implicatively by the three other variables [(Comfort/Functionality => Control/privacy) => Workplace attachment] => job satisfaction.  相似文献   
56.
Ethnic identity is defined in terms of the interaction between exploration of and commitment to a given cultural background. The present study investigated the effect of individual background, role transitions, and the social environment on the development of ethnic identity in a sample of German adults aged 21–73 years (N = 2,940). Additionally, identity transitions and the moderating effect of disequilibrating life events on identity over time were examined (N = 827). Overall, results are consistent with findings for other identity domains: Respondents could be assigned to one of four identity stages, ranging from unexamined to achieved identity. Particularly, the individual background and the extent of community involvement affected ethnic identity formation in adulthood. Longitudinal analyses revealed that only one-third of respondents had remained in the same identity stage; most individuals had transitioned forward or backward. Changes in ethnic identity were not moderated by disequilibrating life events.  相似文献   
57.
宋枝璘  郭磊  郑天鹏 《心理学报》2022,54(4):426-440
数据缺失在测验中经常发生, 认知诊断评估也不例外, 数据缺失会导致诊断结果的偏差。首先, 通过模拟研究在多种实验条件下比较了常用的缺失数据处理方法。结果表明:(1)缺失数据导致估计精确性下降, 随着人数与题目数量减少、缺失率增大、题目质量降低, 所有方法的PCCR均下降, Bias绝对值和RMSE均上升。(2)估计题目参数时, EM法表现最好, 其次是MI, FIML和ZR法表现不稳定。(3)估计被试知识状态时, EM和FIML表现最好, MI和ZR表现不稳定。其次, 在PISA2015实证数据中进一步探索了不同方法的表现。综合模拟和实证研究结果, 推荐选用EM或FIML法进行缺失数据处理。  相似文献   
58.
Considering the high crash rates involving pedestrians on urban roads, it is highly relevant to understanding pedestrian crossing behavior. This paper is the first to combine stated preference (SP) and revealed preference (RP) data to evaluate the impact that individual attributes, trip characteristics, built environment, strategies to prevent unauthorized crossing, and traffic flows have on pedestrians crossing decisions in an urban context. SP and RP surveys were designed and collected in Barranquilla (Colombia) near pedestrian bridges or signalized intersections where direct crossings and a high concentration of pedestrian fatalities related to traffic accidents exist. A logit model was estimated using the data enrichment paradigm. Results show that pedestrians weigh risks and costs when choosing how to cross the road. The trajectories observed in the RP component suggest that people prefer direct crossings; nevertheless, pedestrian bridges and signalized intersections can be attractive alternatives if their location matches the origin or destination of the crossing, and no detour is needed to use them. Waiting time; safety; the fine imposed for jaywalking; personal security, and previous decisions are also variables that influence pedestrian behavior when crossing urban roads. These results can be helpful to urban planners and decision-makers interested in proposing appropriate pedestrian infrastructure. The data pooling technique and the inclusion of a cost-related variable (i.e., fine) allowed computing the willingness to pay and marginal substitution rates for attributes of the built environment and other characteristics associated with the crossing decision. Also, the inclusion of several crossing alternatives and situations allowed assessing pedestrian crossing preferences under different scenarios.  相似文献   
59.
在心理学和其他社科研究领域, 大量实证文章建立调节效应模型, 以分析自变量对因变量的影响是如何随着调节变量的变化而改变。过去10多年, 调节效应分析成了方法学研究的一个热点。从显变量的调节效应、潜变量的调节效应、多层数据的调节效应、基于两层回归模型的单层调节分析、纵向数据的调节效应、调节和中介的整合模型六个主题系统地总结了国内调节效应分析的方法学研究的发展历程。最后对调节效应的未来研究方向做了讨论和拓展。  相似文献   
60.
探究带宽选择方法、样本量、题目数量、等值设计、数据模拟方式对项目反应理论观察分数核等值的影响。通过两种数据模拟方式,获得研究数据,并计算局部与全域评价指标。研究发现,在随机组设计中,带宽选择方法表现相似;考生样本量和题目数量影响甚微。在非等组设计中,惩罚法与Silverman经验准则表现优异;增加题目量可降低百分相对误差和随机误差;增加样本量导致百分相对误差变大,随机误差减小。数据模拟方式可影响等值评价。未来应重点关注等值系统评估。  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