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   4744篇
  免费   237篇
  2023年   43篇
  2022年   42篇
  2021年   77篇
  2020年   90篇
  2019年   127篇
  2018年   164篇
  2017年   168篇
  2016年   193篇
  2015年   127篇
  2014年   148篇
  2013年   575篇
  2012年   226篇
  2011年   259篇
  2010年   162篇
  2009年   142篇
  2008年   211篇
  2007年   178篇
  2006年   163篇
  2005年   135篇
  2004年   164篇
  2003年   154篇
  2002年   128篇
  2001年   88篇
  2000年   92篇
  1999年   64篇
  1998年   54篇
  1997年   47篇
  1996年   33篇
  1995年   32篇
  1994年   31篇
  1993年   28篇
  1992年   45篇
  1991年   36篇
  1990年   57篇
  1989年   53篇
  1988年   49篇
  1987年   29篇
  1986年   42篇
  1985年   44篇
  1984年   40篇
  1983年   30篇
  1982年   34篇
  1981年   29篇
  1980年   26篇
  1979年   29篇
  1978年   27篇
  1977年   18篇
  1976年   18篇
  1975年   22篇
  1974年   26篇
排序方式: 共有4981条查询结果,搜索用时 15 毫秒
21.
Subjects adjusted a local gauge figure such as to perceptually "fit" the apparent surfaces of objects depicted in photographs. We obtained a few hundred data points per session, covering the picture according to a uniform lattice. Settings were repeated 3 times for each of 3 subjects. Almost all of the variability resided in the slant; the relative spread in the slant was about 25% (Weber fraction). The tilt was reproduced with a typical spread of about 10 degrees. The rank correlation of the slant settings of different observers was high, thus the slant settings of different subjects were monotonically related. The variability could be predicted from the scatter in repeated settings by the individual observers. Although repeated settings by a single observer agreed within 5%, observers did not agree on the value of the slant, even on the average. Scaling factors of a doubling in the depth dimension were encountered between different subjects. The data conformed quite well to some hypothetical fiducial global surface, the orientation of which was "probed" by the subject's local settings. The variability was completely accounted for by single-observer scatter. These conclusions are based upon an analysis of the internal structure of the local settings. We did not address the problem of veridicality, that is, conformity to some "real object."  相似文献   
22.
This paper suggests a method to supplant missing categorical data by reasonable replacements. These replacements will maximize the consistency of the completed data as measured by Guttman's squared correlation ratio. The text outlines a solution of the optimization problem, describes relationships with the relevant psychometric theory, and studies some properties of the method in detail. The main result is that the average correlation should be at least 0.50 before the method becomes practical. At that point, the technique gives reasonable results up to 10–15% missing data.We thank Anneke Bloemhoff of NIPG-TNO for compiling and making the Dutch Life Style Survey data available to use, and Chantal Houée and Thérèse Bardaine, IUT, Vannes, France, exchange students under the COMETT program of the EC, for computational assistance. We also thank Donald Rubin, the Editors and several anonymous reviewers for constructive suggestions.  相似文献   
23.
The development of competence was studied in a longitudinal sample of 98 children, with measurement points when the children were 7, 10, and 12 years old. Competence was defined in terms of adequate adaptation to developmental tasks, both on a general and on a domain-specijic level. The general form of competence was measured by ego-resiliency, reflecting fexibility and ability to solve developmental problems Domain-specific competencies were measured by school achievement and social preference. The results showed that ego-resiliency was related to the two domain-specific competencies, although the hypothesized causal direction from general competence to specific competencies was not supported. Both domain-specific competencies were found to have a feedback effect on ego-resiliency. This feedback effect was stronger for social preference. These results suggest a transactional relationship between general and domain-specific competencies, and point to the importance of domain-specific competencies (especially social preference by the peer group) in the development of general competence in the child.  相似文献   
24.
Kelley and Stahelski's (1970) triangle hypothesis states that competitors hold homogeneous views of others by assuming that most others are competitive, whereas cooperators or pro-social people hold more heterogeneous views by assuming that others are either cooperative or competitive. To evaluate the triangle hypothesis, this study examines differences between pro-socials, individualists, and competitors not only in their expectations about others' choice behaviour, but also in the confidence with which such expectations are held. It was found that pro-social subjects expected more cooperation than individualists and competitors. More importantly, as predicted on the basis of the triangle hypothesis, pro-socials were less confident about their expectations than competitors, with individualists holding intermediate levels of confidence.  相似文献   
25.
The Additive Factor Method assumes that task performance is the sum of sequential and independent processes. We studied the duration of the central processes (memory search and decision) and the motor decision process in hyperactive and learning-disabled children under socalled divided attention and S-R compatibility conditions. It was found that the learning-disabled were impaired in memory search and decision processes whereas hyperactives were impaired in the motor decision process.The authors wish to thank L. Leertouwer for making the drawings.  相似文献   
26.
27.
Using neutral stimuli (mushrooms and flowers) and phobia-relevant stimuli (snakes and spiders), the present investigation examined the effect of gaze shifts on subjective evaluation of stimuli in female subjects (N = 29). One group of subjects had to orient to the right, whereas the other group had to orient to the left in order to see the stimuli. When left-handed subjects were excluded from the analysis, the results showed that subjects in the 'orient right' group gave a significantly more positive evaluation than subjects in the 'orient left' group. The results provide a replication of the phenomenon described by Drake (1987).  相似文献   
28.
Restrained eaters are rapidly habituating sensation seekers   总被引:1,自引:0,他引:1  
Several authors have pointed to similarities between eating disorders and addictive behaviors. In earlier studies, addicts were found to score high on the Sensation Seeking Scale (SSS) and to habituate rapidly to neutral stimuli. In this study, we found experimental support for an addiction model of eating disorders: restrained eaters also scored significantly higher on the Sensation Seeking Scale and also habituated significantly quicker to a series of neutral stimuli than unrestrained eaters. No clear evidence was found for the hypothesis that restrained eaters score lower on measurements of anxiety. It is hypothesized that rapid habituation promotes sensation seeking, which may be manifested in excessive consumption of either drugs or food. Restraint may be a strategy to prevent negative consequences of sensation seeking and excessive consumption. The model is related to earlier experimental findings.  相似文献   
29.
Although there has been a considerable amount of research on simultaneous and successive processing (Luria's second functional unit) by Das and others, there have been relatively few investigations into the measurement of attention and planning (the first and third functional units, respectively). The purpose of this investigation was to examine the factorial validity of tasks designed to measure cognitive processing in each of Luria's three functional units. A sample of 112 normal fourth- and fifth-grade students were administered nine experimental tasks chosen or developed according to the theoretical components of planning, attention, simultaneous, and successive processes. Principal factor analyses (orthogonal and oblique) with rotation of four factors resulted in solutions that closely matched the anticipated groupings based on a structural analysis of the tasks. General support for the feasibility of measurement of Luria's cognitive processing model, and the need to further develop and refine these and other experimental tasks, was obtained.  相似文献   
30.
This study investigated attitude-behavior relationships in the context of energy conservation. Results indicated that general environmental concern is a poor predictor of energy-conservation behaviors. Direct evaluative comparisions of various non-conservationist behaviors with a more conservationist alternative showed a clear relationship with behavioral preference. Non-conservationists, however, evaluated their own behavior only marginally favorably and in some cases clearly unfavorably. This was accompanied by an overestimation of the common occurrence of these behaviors among the general population and by an unwillingness to relate these behaviors to personality characteristics. It is argued that these biases (i.e., considering one's behavior as a habit that is shared by many others) could hinder behavioral change. These findings are discussed in terms of effective public policy on the issue of energy consumption.  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