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   482篇
  免费   21篇
  503篇
  2022年   3篇
  2021年   5篇
  2020年   7篇
  2019年   7篇
  2018年   8篇
  2017年   10篇
  2016年   22篇
  2015年   14篇
  2014年   14篇
  2013年   50篇
  2012年   25篇
  2011年   29篇
  2010年   12篇
  2009年   12篇
  2008年   18篇
  2007年   28篇
  2006年   22篇
  2005年   10篇
  2004年   15篇
  2003年   13篇
  2002年   17篇
  2001年   9篇
  2000年   4篇
  1999年   3篇
  1998年   4篇
  1997年   5篇
  1996年   5篇
  1995年   3篇
  1994年   5篇
  1993年   3篇
  1992年   9篇
  1991年   9篇
  1990年   5篇
  1989年   6篇
  1988年   5篇
  1985年   3篇
  1984年   4篇
  1983年   3篇
  1982年   3篇
  1981年   3篇
  1980年   3篇
  1978年   5篇
  1976年   4篇
  1974年   10篇
  1971年   3篇
  1969年   3篇
  1968年   6篇
  1957年   4篇
  1956年   5篇
  1955年   4篇
排序方式: 共有503条查询结果,搜索用时 62 毫秒
101.
To test the hypothesis that pigeons will only code the more salient sample when samples differ markedly in salience, pigeons were trained with samples consisting of a 2-s presentation of food (highly salient sample) and an 8-s presentation of keylight (less salient sample). During retention testing, pigeons tended to respond at longer delays as if an 8-s keylight sample had been presented. This finding is consistent with use of a single-code/default strategy in which only the 2-s food sample was coded and the comparison associated with an 8-s keylight sample was selected by default in the absence of memory for the salient 2-s food sample. Hence, a marked difference in sample salience appears to encourage use of a single-code/default strategy.  相似文献   
102.
This study examined the experiences of a sample of skilled immigrants to Canada from Asia and Africa who were currently experiencing credentialing problems (N?=?180). Most respondents had advanced postsecondary training and a job requiring a high level of skill prior to emigrating, but many were unable to obtain equivalent work in Canada. In reaction, they took work for which they were overqualified, volunteered, had their qualifications assessed, and upgraded their training. Most respondents were surprised and upset that it was so difficult for them to obtain a suitable job in their profession, and many felt that immigrants were discriminated against by Canadian employers. The policy implications of this “brain waste” are discussed.  相似文献   
103.
Jaccard has been the choice similarity metric in ecology and forensic psychology for comparison of sites or offences, by species or behaviour. This paper applies a more powerful hierarchical measure—taxonomic similarity (Δs), recently developed in marine ecology—to the task of behaviourally linking serial crime. Forensic case linkage attempts to identify behaviourally similar offences committed by the same unknown perpetrator (called linked offences). Δs considers progressively higher‐level taxa, such that two sites show some similarity even without shared species. We apply this index by analysing 55 specific offence behaviours classified hierarchically. The behaviours are taken from 16 sexual offences by seven juveniles where each offender committed two or more offences. We demonstrate that both Jaccard and Δs show linked offences to be significantly more similar than unlinked offences. With up to 20% of the specific behaviours removed in simulations, Δs is equally or more effective at distinguishing linked offences than where Jaccard uses a full data set. Moreover, Δs retains significant difference between linked and unlinked pairs, with up to 50% of the specific behaviours removed. As police decision‐making often depends upon incomplete data, Δs has clear advantages and its application may extend to other crime types. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   
104.
Ramsey G  Bastian ML  van Schaik C 《The Behavioral and brain sciences》2007,30(4):393-407; discussion 407-32
Innovation is a key component of most definitions of culture and intelligence. Additionally, innovations may affect a species' ecology and evolution. Nonetheless, conceptual and empirical work on innovation has only recently begun. In particular, largely because the existing operational definition (first occurrence in a population) requires long-term studies of populations, there has been no systematic study of innovation in wild animals. To facilitate such study, we have produced a new definition of innovation: Innovation is the process that generates in an individual a novel learned behavior that is not simply a consequence of social learning or environmental induction. Using this definition, we propose a new operational approach for distinguishing innovations in the field. The operational criteria employ information from the following sources: (1) the behavior's geographic and local prevalence and individual frequency; (2) properties of the behavior, such as the social role of the behavior, the context in which the behavior is exhibited, and its similarity to other behaviors; (3) changes in the occurrence of the behavior over time; and (4) knowledge of spontaneous or experimentally induced behavior in captivity. These criteria do not require long-term studies at a single site, but information from multiple populations of a species will generally be needed. These criteria are systematized into a dichotomous key that can be used to assess whether a behavior observed in the field is likely to be an innovation.  相似文献   
105.
106.
Relationships among competition, athletic skill, and social relationships among children have received considerable attention from social psychologists and have also sparked considerable public debate. Most studies of these relationships have concentrated on sports programs involving upper elementary or older boys. This field work study examined these relationships in three after-school recreation programs for children ages 5 to 8. Although all programs professed to stress skills development over competition, teams act varied substantially in competitive climates. Competitive environments heightened the tendency for athletic skill to function as a generalized status element in peer networks. After-school sports programs contributed to the reproduction of athletic skill as a basis of peer status, even for young children.  相似文献   
107.
108.
109.
Samples of 56 male certified public accounting firm employees and 24 male accounting undergraduate students were given the CPI to test for subgroup differences in personality traits. The samples were also compared with eight occupational groups reported in the CPI manual. A statistical analysis of CPI scale mean score differences indicates a dichotomy of the accounting sample with the older accountants more conservative, conforming and restrictive than the younger accountants.  相似文献   
110.
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