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   6438篇
  免费   298篇
  国内免费   2篇
  2020年   76篇
  2019年   97篇
  2018年   123篇
  2017年   127篇
  2016年   129篇
  2015年   116篇
  2014年   121篇
  2013年   573篇
  2012年   223篇
  2011年   235篇
  2010年   148篇
  2009年   142篇
  2008年   169篇
  2007年   162篇
  2006年   156篇
  2005年   133篇
  2004年   124篇
  2003年   118篇
  2002年   131篇
  2001年   213篇
  2000年   202篇
  1999年   165篇
  1998年   59篇
  1993年   57篇
  1992年   115篇
  1991年   112篇
  1990年   109篇
  1989年   95篇
  1988年   90篇
  1987年   93篇
  1986年   99篇
  1985年   105篇
  1984年   92篇
  1983年   72篇
  1981年   57篇
  1980年   57篇
  1979年   113篇
  1978年   60篇
  1977年   53篇
  1976年   66篇
  1975年   77篇
  1974年   105篇
  1973年   91篇
  1972年   76篇
  1971年   79篇
  1970年   77篇
  1969年   81篇
  1968年   76篇
  1967年   90篇
  1966年   52篇
排序方式: 共有6738条查询结果,搜索用时 15 毫秒
991.
A mechanical device is described which materially reduces the time, labor, and probability of errors which are involved in the computation of certain moments about the mean. The use of the device is illustrated with the computation of the mean, standard deviation,g 1 as a measure of skewness, andg 2 as a measure of kurtosis of data from a given study.Grateful acknowledgment is made to the Holter Research Foundation of Helena, Montana for the grant-in-aid which made possible the development of this device.  相似文献   
992.
993.
994.
995.
The rate at which monkeys pressed a lever and avoided shocks was manipulated in several ways. Measurements were also made of their plasma levels of 17-hydroxycorticosteroids. The rate at which the animals pressed the lever and the frequency with which they received shocks were both implicated as determiners of the steroid levels.  相似文献   
996.
A criticism leveled against the conceptualization of emotional intelligence (EI) as a personality trait is that it overlaps considerably with the higher order personality dimensions and, therefore, has weak utility. To investigate this criticism, a systematic review and meta-analysis were conducted to synthesize the literature examining the incremental validity of the 2 adult self-report forms of the Trait Emotional Intelligence Questionnaire (TEIQue). Twenty-four articles reporting 114 incremental validity analyses of the TEIQue were reviewed according to the studies' methodological features. Additionally, data from 18 studies (providing 105 effect sizes) were pooled in a meta-analysis. Results suggest that the TEIQue consistently explains incremental variance in criteria pertaining to different areas of functioning, beyond higher order personality dimensions and other emotion-related variables. The pooled effect size was relatively small, but statistically and practically significant (ΔR2 = .06, SE = .0116; 95% CI [.03, .08]). The number of covariates controlled for, the form of the TEIQue, and the focus on higher order personality dimensions versus other individual-difference constructs as baseline predictors did not affect the effect size. Analyses conducted at the factor level indicated that the incremental contribution is mainly due to the well-being and self-control factors of trait EI. Methodological issues and directions for future research are discussed.  相似文献   
997.
This study evaluates sex differences in the perceived desirability of personality behaviors and beliefs. Men and women (N = 149, Mage = 18.7) judged the social desirability scale values (SDSVs) of 150 personality statements as applied either to a male target or a female target. For comparison, some estimated SDSVs with no target sex specified. A separate sample of 537 respondents endorsed the 150 items via self‐report. Raters showed a high consensus in their SDSV judgments within conditions (α = .86 to .90) and no sex‐of‐rater effects across conditions. Substantial sex‐of‐target effects (p < .001), however, revealed many behaviors that were viewed as desirable for one sex but not for the other. The behaviors seen as more (less) desirable when applied to men rather than to women were endorsed more (less) by men than by women in the respondent sample. Similar results were found when no target sex was specified for the SDSV ratings, presumably because judges evaluated the behaviors as applied to a target of their own sex. The present results have important implications for the measurement and reporting of SDSVs, the evaluation of substance versus style in self‐reports, and the construction of desirability‐reduced personality inventories.  相似文献   
998.
Human delay discounting is usually studied with experimental protocols that use symbols to express delay and amount. In order to further understand discounting, we evaluated whether the absence of numbers to represent reward amounts affects discount rate in general, and whether the magnitude effect is generalized to nonsymbolic situations in particular. In Experiment 1, human participants were exposed to a delay‐discounting task in which rewards were presented using dots to represent monetary rewards (nonsymbolic); under this condition the magnitude effect did not occur. Nevertheless, the magnitude effect was observed when equivalent reward amounts were presented using numbers (symbolic). Moreover, in estimation tasks, magnitude increments produced underestimation of large amounts. In Experiment 2, participants were exposed only to the nonsymbolic discounting task and were required to estimate reward amounts in each trial. Consistent with Experiment 1, the absence of numbers representing reward amounts produced similar discount rates of small and large rewards. These results suggest that value of nonsymbolic rewards is a nonlinear function of amount and that value attribution depends on perceived difference between the immediate and the delayed nonsymbolic rewards.  相似文献   
999.
The purpose of this study was to investigate cultural differences between Danish and American children at 2 and 3 years as measured with the developmental test Bayley‐III, and to investigate the Bayley‐III Language Scale validity. The Danish children (N = 43) were tested with the Bayley‐III and their parents completed an additional language questionnaire (the MacArthur‐Bates CDI). Results showed that scores from the Danish children did not differ significantly from the American norms on the Cognitive or Motor Scale, but the Danish sample scored significantly higher on the Language Scale. A comparison of the Bayley‐III Language subtests with the CDI showed that the two measures correlated significantly, but the percentile score from the CDI was significantly higher than the percentile score from the Bayley‐III Language subtests. This could be because the two instruments measure slightly different areas of language development, or because the Bayley‐III overestimates language development in Danish children. However, due to the limitations of the current study, further research is needed to clarify this issue.  相似文献   
1000.
Perceptual similarity is an important property of multiple stimuli. Its computation supports a wide range of cognitive functions, including reasoning, categorization, and memory recognition. It is important, therefore, to determine why previous research has found conflicting effects of inter-item similarity on visual working memory. Studies reporting a similarity advantage have used simple stimuli whose similarity varied along a featural continuum. Studies reporting a similarity disadvantage have used complex stimuli from either a single or multiple categories. To elucidate stimulus conditions for similarity effects in visual working memory, we tested memory for complex stimuli (faces) whose similarity varied along a morph continuum. Participants encoded 3 morphs generated from a single face identity in the similar condition, or 3 morphs generated from different face identities in the dissimilar condition. After a brief delay, a test face appeared at one of the encoding locations for participants to make a same/different judgment. Two experiments showed that similarity enhanced memory accuracy without changing the response criterion. These findings support previous computational models that incorporate featural variance as a component of working memory load. They delineate limitations of models that emphasize cortical resources or response decisions.  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