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   8768篇
  免费   565篇
  国内免费   151篇
  2023年   87篇
  2022年   54篇
  2021年   93篇
  2020年   221篇
  2019年   220篇
  2018年   176篇
  2017年   184篇
  2016年   196篇
  2015年   140篇
  2014年   133篇
  2013年   495篇
  2012年   125篇
  2011年   113篇
  2010年   93篇
  2009年   123篇
  2008年   134篇
  2007年   149篇
  2006年   134篇
  2005年   120篇
  2004年   111篇
  2003年   89篇
  2002年   87篇
  2001年   69篇
  2000年   71篇
  1999年   60篇
  1998年   43篇
  1997年   49篇
  1996年   46篇
  1995年   35篇
  1994年   31篇
  1993年   36篇
  1992年   39篇
  1991年   17篇
  1990年   20篇
  1989年   26篇
  1987年   17篇
  1986年   17篇
  1985年   450篇
  1984年   523篇
  1983年   427篇
  1982年   533篇
  1981年   501篇
  1980年   528篇
  1979年   472篇
  1978年   509篇
  1977年   388篇
  1976年   384篇
  1975年   323篇
  1974年   308篇
  1973年   254篇
排序方式: 共有9484条查询结果,搜索用时 15 毫秒
91.
Six pigeons were trained in a discrete-trials signal-detection procedure to discriminate between a fixed-duration stimulus (5 s or 20 s) and a set of variable durations ranging from 2.5 s to 57.5 s in steps of 5 s. For each fixed-duration stimulus, the ratio of reinforcer frequencies contingent upon reporting the fixed versus the variable stimulus was systematically manipulated. Detection performance was well controlled by both the stimulus value and the reinforcer ratio. Both the discriminability between the fixed duration and the set of variable durations, and the discriminability between the fixed duration and each of the variable durations, were independent of the reinforcer-frequency ratio when discriminability was measured as log d. The sensitivity of response bias to reinforcement-ratio changes was independent of the value of the fixed duration, but was not independent of the discriminability of the variable durations from the fixed durations. Under current models, discriminability measures in complex temporal discrimination may be independent of biasing manipulations, but bias measures are not independent of stimulus values.  相似文献   
92.
Two cynomolgous macaques categorized six colors into two groups of three after conditional discrimination training (zero-delay symbolic match-to-sample). The procedures resulted in the establishment of relations among the elements of each set-relations that were not specifically trained and that can be characterized by the properties of reflexivity, symmetry, and transitivity. Each set of colors was related to a characteristic pattern of responding: One response pattern involved temporal duration (press and hold the response keys); the second response pattern entailed repeated pressing and releasing of the response keys (fixed ratio 8). Six combinations of two colors were trained, three combinations from each set. After discriminative performance stabilized for each monkey, they were tested with 10 additional color combinations, all of which differed from the training combinations. The conditional relations established between test combinations can be characterized as stimulus equivalence. The training procedures were analogous to the procedure of using category names, and have implications for understanding the function of language in the formation of equivalence classes.  相似文献   
93.
Interventions were employed to program maintenance following correspondence training. The use of reinforcement of verbalization and a mixed sequence of procedures designed to establish indiscriminable contingencies was evaluated in multiple-baseline designs across subjects and behaviors. The results indicated that target behaviors were maintained under less intrusive interventions and in the absence of programmed contingencies during extended follow-up conditions. The results are discussed in terms of changes in reinforcement schedules established in maintenance interventions.  相似文献   
94.
The possible role of "effort" in the accuracy of pigeons' performance on a delayed matching-to-sample procedure was investigated by examining the effects of response requirements that accompanied a trial-initiating stimulus and that accompanied a sample stimulus. In the first experiment, the effect of varying the size of a fixed-ratio requirement for responses during an initiating stimulus was compared to that of varying a similar requirement for responses during the sample stimulus. Accuracy increased reliably with increases in the ratio scheduled during the sample stimulus, but was not significantly affected by increases in the ratio scheduled on the key during the initiating stimulus. In another phase of Experiment 1, sample duration was held constant while the ratio requirement was varied during the initiating stimulus. Again, accuracy of matching to sample was not significantly affected by the size of the ratio scheduled during the initiating stimulus. Experiment 2 provided a systematic replication of these results in another group of pigeons and included a more detailed analysis of responding. These results support the view that increases in sample-response requirement facilitate accuracy of delayed matching by increasing the durations of exposure to the sample stimuli, and do not support a role of effort in the sample-response effect. In Experiment 3, the facilitative effect of responses on the sample but not of those on the initiating stimulus was replicated using a simultaneous matching-to-sample procedure. This finding provides further evidence against an interpretation of response-requirement effects that appeals to effort; the finding also suggests that sample exposure might affect initial discrimination of the sample rather than remembering the sample.  相似文献   
95.
Generalization of four retarded children's object naming responses to stimuli in the natural environment was assessed after training with either objects or pictures of the objects. Generalization was typically greater after training with objects. In a second experiment, half of the stimuli that showed little generalization were retrained by alternating the original training object with an object that belonged to the same stimulus class as the training stimulus. The other half were simply retrained using the object. The alternating procedure resulted in substantial increases in generalization to untrained objects.  相似文献   
96.
We examined the effects of behavioral procedures to modify the food choices of preschoolers during a snack period at school (training setting) and at home (generalization setting). In the first experiment, we evaluated the usefulness of nutrition training and a generalization programming strategy of cueing to improve healthy snacking; in the second experiment we investigated the effect of nutrition training alone. In addition, three cases are presented that illustrate individualized procedures to facilitate generalization of healthy snacking to home. Results indicated that children's healthy snack choices increased in the preschool training setting, that generalization to home was achieved only when procedures to program it were implemented, and that the best results were found when the generalization procedures were tailored to the individual child.  相似文献   
97.
The need to train accurate, not necessarily agreeing, observers is discussed. Intraobserver consistency as an intermediate criterion in such training is proposed and contrasted with the more familiar criterion of interobserver agreement. Videotaped observations of social interactions between handicapped and nonhandicapped preschoolers provided the medium for examining the criterion agreement of four observers trained against each type of standard. Observers generally failed to show high levels of criterion agreement whether trained to a within- or to a between-observer agreement standard. The results varied somewhat with the frequency of behaviors, however. Correlations between interobserver agreement and intraobserver consistency were variable but somewhat higher when interobserver agreement was the training criterion than when intraobserver consistency was the criterion. Correlations between interobserver agreement and criterion agreement ranged from — .16 to .89 during interobserver agreement training. Correlations between intraobserver consistency and criterion agreement ranged from — .23 to .99 during intraobserver consistency training.  相似文献   
98.
A measure of agreement for partially ordered data is suggested that makes use of the k categories with the highest ranks, the ranks of the remaining categories being disregarded. The proposed measure is applied to the Self-Directed Search in order to evaluate its agreement with occupational preference. Other forms of agreement in the Holland classification system can also be assessed by the proposed measure. Examples are congruence and husband-wife and counselor-client agreement.  相似文献   
99.
In the first experiment, subjects rated the similarity of a sample of pairs of random dot patterns generated from 3 prototypes consisting of either 4, 6, or 9 dots. The results of the experiment tended to confirm the structure imposed on the patterns by the construction method. In the second experiment, subjects learned to classify random patterns generated from 2 prototypes with either short or long interprototype distance and consisting of either 4, 6, or 9 dots in a traditional concept identification task. After acquisition, memory for old and new distortions and the prototype, which was not presented during learning, was assessed. The tendency to call a pattern “new” increased with the distance between the pattern and its prototype. In a subsequent transfer test, all subjects saw patterns of either 4, 6, or 9 dots. Performance was above chance and the transfer from larger to smaller patterns tended to be greater than the transfer from smaller to larger patterns. This is consistent with a process of schema formation based on features common to most exemplars of the category. The results are discussed in relation to several theories of concept learning and schema abstraction.  相似文献   
100.
This study examined changes in cognitive-dissonance-related variables during the professional training period. Differences in levels and change in satisfaction with career choice, importance of career, certainty of career decision, self-occupational perceptions, general attitude toward career, time since career decision, and past experience were observed when students who left a collegiate professional training program before program completion were compared with those who remained in the program. Data supports the validity of D. Hershenson and R. Roth's (1966, Journal of Counseling Psychology, 13, 368–370) and V. Harren's (1979, Journal of Vocational Behavior, 14, 119–133) theoretical models of vocational decision and the Assessment of Career Decision Making scale.  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