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   861篇
  免费   638篇
  国内免费   24篇
  1523篇
  2024年   5篇
  2023年   15篇
  2021年   20篇
  2020年   50篇
  2019年   54篇
  2018年   36篇
  2017年   43篇
  2016年   42篇
  2015年   33篇
  2014年   42篇
  2013年   48篇
  2012年   36篇
  2011年   47篇
  2010年   37篇
  2009年   46篇
  2008年   40篇
  2007年   32篇
  2006年   29篇
  2005年   29篇
  2004年   34篇
  2003年   37篇
  2002年   36篇
  2001年   34篇
  2000年   38篇
  1999年   27篇
  1998年   33篇
  1997年   28篇
  1996年   27篇
  1995年   21篇
  1994年   31篇
  1993年   30篇
  1992年   26篇
  1991年   22篇
  1990年   29篇
  1989年   12篇
  1988年   28篇
  1987年   31篇
  1986年   17篇
  1985年   20篇
  1984年   22篇
  1983年   25篇
  1982年   20篇
  1981年   26篇
  1980年   29篇
  1979年   29篇
  1978年   33篇
  1977年   33篇
  1976年   39篇
  1975年   20篇
  1974年   1篇
排序方式: 共有1523条查询结果,搜索用时 15 毫秒
211.
Political scientists are increasingly exploring the psychological underpinnings of voting behavior using field experimental techniques. Research in psychology demonstrates that positive reinforcement—what I describe as positive social pressure—motivates prosocial behavior. A distinctive feature of the current study is the focus on key subgroups of voters, namely unmarried women and minorities. Attention to these voter subgroups allows us to build upon findings reported in previous studies that leave questions about the generalizability of the reported effects of positive social pressure to key demographic subgroups of voters largely unanswered. This article reports the results of a large‐scale randomized field experiment designed to investigate the impact of positive social pressure on voter turnout. The experiment was conducted during the November 2009 gubernatorial election in New Jersey, and the results suggest positive social pressure mobilizes voters. Moreover, the effects appear to be robust across subgroups of voters, including minorities and unmarried women, and both lower‐ and higher‐propensity voters.  相似文献   
212.
ABSTRACT

Fractions are defined by numerical relationships, and comparing two fractions’ magnitudes requires within-fraction (holistic) and/or between-fraction (componential) relational comparisons. To better understand how individuals spontaneously reason about fractions, we collected eye-tracking data while they performed a fraction comparison task with conditions that promoted or obstructed different types of comparisons. We found evidence for both componential and holistic processing in this mixed-pairs task, consistent with the hybrid theory of fraction representation. Additionally, making within-fraction eye movements on trials that promoted a between-fraction comparison strategy was associated with slower responses. Finally, participants who performed better on a non-numerical test of reasoning took longer to respond to the most difficult fraction trials, which suggests that those who had greater facility with non-numerical reasoning attended more to numerical relationships. These findings extend prior research and support the continued investigation into the mechanistic links between numerical and non-numerical reasoning.  相似文献   
213.
Feedback-based learning declines with age. Because older adults are generally biased toward positive information (“positivity effect”), learning from positive feedback may be less impaired than learning from negative outcomes. The literature documents mixed results, due possibly to variability between studies in task design. In the current series of studies, we investigated the influence of feedback valence on reinforcement learning in young and older adults. We used nonprobabilistic learning tasks, to more systematically study the effects of feedback magnitude, learning of stimulus–response (S–R) versus stimulus–outcome (S–O) associations, and working-memory capacity. In most experiments, older adults benefitted more from positive than negative feedback, but only with large feedback magnitudes. Positivity effects were pronounced for S–O learning, whereas S–R learning correlated with working-memory capacity in both age groups. These results underline the context dependence of positivity effects in learning and suggest that older adults focus on high gains when these are informative for behavior.  相似文献   
214.
Previous studies have demonstrated that discriminative learning is facilitated when a particular outcome is associated with each relation to be learned. When this training procedure is applied (the differential outcomes procedure; DOP), learning is faster and better than when the typical common outcomes procedure or nondifferential outcomes (NDO) is used. Our primary purpose in the two experiments reported here was to assess the potential advantage of DOP in 5-year-old children using three different strategies of reinforcement in which (a) children received a reinforcer following a correct choice (“ + ”), (b) children lost a reinforcer following an incorrect choice (“ ? ”), or (c) children received a reinforcer following a correct choice and lost one following an incorrect choice (“ + / ? ”). In Experiment 1, we evaluated the effects of the presence of DOP and different types of reinforcement on learning and memory of a symbolic delayed matching-to-sample task using secondary and primary reinforcers. Experiment 2 was similar to the previous one except that only primary reinforcers were used. The results from these experiments indicated that, in general, children learned the task faster and showed higher performance and persistence of learning whenever differential outcomes were arranged independent of whether it was differential gain, loss, or combinations. A novel finding was that they performed the task better when they lost a reinforcer following an incorrect choice (type of training “ ? ”) in both experiments. A further novel finding was that the advantage of the DOP over the nondifferential outcomes training increased in a retention test.  相似文献   
215.
Numerals are processed by a phylogenetically old analogue magnitude system. Can culturally new negative numerals be processed using this same representation? To find out whether magnitude representation could be used, we contrasted three possible processing mechanisms: an extended magnitude system for both positive and negative numbers, a mirroring mechanism that could transform negative values to the positive range to be processed on the positive magnitude system, and a sign shortcut strategy that can process the signs of numbers independently of the absolute values of numerals. To test these three hypotheses, a comparison task was used and the reaction time pattern, numerical distance, and Spatial-Numerical Association of Response Codes (SNARC) effect was analysed. The results revealed a mirroring process along with a sign shortcut mechanism. The SNARC effect was observed only when positive numbers were compared.  相似文献   
216.
This study evaluated the extent to which a conjugate reinforcement schedule (CONJ) involving a contingency between pedaling a stationary bike and viewing a preferred movie could serve as a translational preparation for the analysis of automatically reinforced behavior. In part, researchers examined whether providing participants with either an accurate or an inaccurate rule about the extinction (EXT) component of a multiple schedule (MULT) contributed to the development of control by the MULT (CONJ EXT) schedule. Results show schedule control emerged for four of five participants who received the accurate rule and none of the five participants who received the inaccurate rule. In addition, participants who received accurate rules typically increased pedaling during CONJ components that followed two consecutive EXT components, suggesting that they experienced deprivation for audio and visual stimulation generated by pedaling. These preliminary findings suggest that researchers could use this translational preparation to identify matched interventions for some automatically reinforced behavior.  相似文献   
217.
218.
Social skills priming was used to increase the spontaneous social initiations of 2 socially withdrawn preschoolers, 1 of whom had been diagnosed with autism. During priming sessions, the teacher prompted and reinforced social behaviors (e.g., smiling, verbal initiations). We varied the rate of reinforcement during priming sessions and measured the effects of this manipulation on the rate of spontaneous social initiations during the subsequent classroom activity. Spontaneous initiations were more frequent after high rates of reinforcement than after low rates of reinforcement.  相似文献   
219.
Human subjects were exposed to a concurrent-chains schedule in which reinforcer amounts, delays, or both were varied in the terminal links, and consummatory responses were required to receive points that were later exchangeable for money. Two independent variable-interval 30-s schedules were in effect during the initial links, and delay periods were defined by fixed-time schedules. In Experiment 1, subjects were exposed to three different pairs of reinforcer amounts and delays, and sensitivity to reinforcer amount and delay was determined based on the generalized matching law. The relative responding (choice) of most subjects was more sensitive to reinforcer amount than to reinforcer delay. In Experiment 2, subjects chose between immediate smaller reinforcers and delayed larger reinforcers in five conditions with and without timeout periods that followed a shorter delay, in which reinforcer amounts and delays were combined to make different predictions based on local reinforcement density (i.e., points per delay) or overall reinforcement density (i.e., points per total time). In most conditions, subjects' choices were qualitatively in accord with the predictions from the overall reinforcement density calculated by the ratio of reinforcer amount and total time. Therefore, the overall reinforcement density appears to influence the preference of humans in the present self-control choice situation.  相似文献   
220.
In Experiment 1, pigeons' pecks on a green key led to a 5-s delay with green houselights, and then food was delivered on 20% (or, in other conditions, 50%) of the trials. Pecks on a red key led to an adjusting delay with red houselights, and then food was delivered on every trial. The adjusting delay was used to estimate indifference points: delays at which the two alternatives were chosen about equally often. Varying the presence or absence of green houselights during the delays that preceded possible food deliveries had large effects on choice. In contrast, varying the presence of the green or red houselights in the intertrial intervals had no effects on choice. In Experiment 2, pecks on the green key led to delays of either 5 s or 30 s with green houselights, and then food was delivered on 20% of the trials. Varying the duration of the green houselights on nonreinforced trials had no effect on choice. The results suggest that the green houselights served as a conditioned reinforcer at some times but not at others, depending on whether or not there was a possibility that a primary reinforcer might be delivered. Given this interpretation of what constitutes a conditioned reinforcer, most of the results were consistent with the view that the strength of a conditioned reinforcer is inversely related to its duration.  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