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   4481篇
  免费   513篇
  国内免费   255篇
  2024年   21篇
  2023年   93篇
  2022年   72篇
  2021年   108篇
  2020年   206篇
  2019年   224篇
  2018年   206篇
  2017年   180篇
  2016年   172篇
  2015年   125篇
  2014年   227篇
  2013年   556篇
  2012年   87篇
  2011年   137篇
  2010年   133篇
  2009年   130篇
  2008年   239篇
  2007年   283篇
  2006年   267篇
  2005年   265篇
  2004年   160篇
  2003年   171篇
  2002年   147篇
  2001年   148篇
  2000年   92篇
  1999年   91篇
  1998年   59篇
  1997年   83篇
  1996年   54篇
  1995年   61篇
  1994年   61篇
  1993年   48篇
  1992年   30篇
  1991年   30篇
  1990年   23篇
  1989年   13篇
  1988年   14篇
  1987年   8篇
  1986年   20篇
  1985年   13篇
  1984年   18篇
  1983年   12篇
  1982年   23篇
  1981年   19篇
  1980年   22篇
  1979年   17篇
  1978年   20篇
  1977年   23篇
  1976年   20篇
  1975年   15篇
排序方式: 共有5249条查询结果,搜索用时 15 毫秒
111.
Results of 1,579 observations of cars entering or exiting campus parking lots showed direct relationships between seat belt wearing and the intrusiveness of the engineering device designed to induce belt usage, and between device intrusiveness and system defeat. For example, all drivers with working interlocks or unlimited buzzer reminders were wearing a seat belt; but 62% of the systems with interlocks or unlimited buzzers had been defeated, and only 15.9% of the drivers in these cars were wearing a seat belt. The normative data indicated marked ineffectiveness of the negative reinforcement contingencies implied by current seat belt inducement systems; but suggested that unlimited buzzer systems would be the optimal system currently available if contingencies were developed to discourage the disconnection and circumvention of such systems. Positive reinforcement strategies are discussed that would be quite feasible for large-scale promotion of seat belt usage.  相似文献   
112.
In the last several years, various organizations have produced strikingly similar documents by which institutions for retarded persons are judged for licensure. The purpose of the present study was to determine whether residential units that were licensed differed from residential units that were not licensed in terms of the active programming behaviors of their staff and residents. Data were collected through a time-sampling procedure that yielded about 160,000 observations on eight staff and six resident behaviors. Results showed that the licensed units were just as derelict as unlicensed units in providing habilitative programming for their retarded residents. Maladaptive responding by residents occurred at least as much as task-related behaviors: residents spent as much time self-stimulating as they did in programming; they also engaged in self-abusive behavior about as much time as they engaged in on-task responding. Results were discussed in terms of the failure of governmental regulations that are not based on observation to adequately assess habilitative programming.  相似文献   
113.
Instrumental treadle press and nonreinforced key peck responses were monitored during discrimination training and generalization testing in pigeons on positive and negative reinforcement schedules. In Experiment 1, six pigeons pressed a treadle for food on a multiple variable-interval extinction schedule. In Experiment 2, three pigeons pressed a treadle to avoid shock on a multiple free-operant avoidance extinction schedule. Different color keylights signaled S+ and S- components. Some positive behavioral contrast occurred during discrimination training, but the effect was small. Pecking occurred to the S+ keylight in Experiment 1 but not in Experiment 2. On stimulus generalization tests, all subjects displayed a positive peak shift when pressing the treadle for food or to avoid shock. However, peak shift was not found for nonreinforced "autopecks" on the stimulus key, although an area shift was observed in Experiment 1. This is the first demonstration of peak shift for pigeons pressing treadles and the only reliable demonstration of peak shift when negative reinforcement maintained responding. These results, in combination with previous demonstrations of peak shift for rats pressing levers and pigeons pecking keys, indicate that peak shift is a general by-product of operant discrimination learning, since it occurs across a variety of the organisms, responses, and reinforcers.  相似文献   
114.
Milligan  Glenn W. 《Psychometrika》1980,45(3):325-342
An evaluation of several clustering methods was conducted. Artificial clusters which exhibited the properties of internal cohesion and external isolation were constructed. The true cluster structure was subsequently hidden by six types of error-perturbation. The results indicated that the hierarchical methods were differentially sensitive to the type of error perturbation. In addition, generally poor recovery performance was obtained when random seed points were used to start theK-means algorithms. However, two alternative starting procedures for the nonhierarchical methods produced greatly enhanced cluster recovery and were found to be robust with respect to all of the types of error examined.  相似文献   
115.
Naturalistic observations were conducted on 19 acutely ill psychiatric patients in the hospital ward milieu. The study was designed to determine relationships between selected social and environment variables and overt atypical behavior. Patients were observed on an individual basis with time-sampling techniques. In total, 16 pathological behaviors were coded and the most frequent (postural deviance, pace, agitation, hyperactivity, withdrawal, foot shake/body sway, leg swing) were selected in order to determine variation in frequency of these behaviors as a function of the following variables: area within hospital, week of hospitalization, distance between the focal subject and his/her nearest neighbor, number of people in an area, and time of day. Results showed differential changes in pathological behavior as a function of week of hospitalization, number of people in a given area, and distance from the focal subject's nearest neighbor. There was no significant change in the frequency of pathological behaviors as a function of area within hospital or time of day. In addition, most pathological behaviors decreased significantly when patients were engaged in the sending or receiving of verbal behavior. Cluster analyses revealed varying degrees of dissociation between pathological behaviors and social-interaction behaviors. These results support (a) a nonunitary concept of the general category pathological and (b) the view that there are inhibitory effects of social interaction on the enactment of atypical behaviors. Clinical implications of these findings are discussed.R.H.P. completed this research during his tenure as a postdoctocal fellow in the Department of Psychiatry, Human Ethology Laboratory, UCLA (NIMH Fellowship 1 F32MHO7627-01). Support for this research also came from the Veterans Administration.  相似文献   
116.
A 7-year-old boy was diagnosed as suffering from childhood depression by two independent psychiatric evaluators who employed the Research Diagnostic Criteria. Multifaceted behavioral observations were performed on target behaviors which were identified as major problematic areas of functioning related to the child's depression. The behavioral assessment strategy included daily monitoring of on-task and disruptive behavior in the classroom, enuresis, and overall hygienic, social, and compliance behaviors as a means of identifying the specific drug-induced effects of an anti-depressant, imipramine. The assimilation and application of behavioral assessment strategies within child psychiatry have been slow and tenuous. Reasons for the resistance include theoretical differences and misconceptions among psychiatric personnel, who, although open to objective evaluations, may wish to employ nonbehavioral treatments such as pharmacologic agents. The primary purpose of this study was to demonstrate the viability of behavioral assessment as an integral adjunct to pharmacologic treatment in a psychiatric setting as a means of gauging the efficacy of a psychiatric intervention. Issues regarding the role of behavioral assessment in psychiatry and, in particular, pharmacologic interventions with depressed children are examined and discussed.This study was supported, in part, by NIMH Grant MH 30915.  相似文献   
117.
Eight pigeons pecked keys under multiple variable-interval two-minute variable-interval two-minute schedules. In Experiment 1, the reinforcers were 2, 4, or 8 seconds access to a food magazine. In Experiments 2 and 3, the reinforcers were grains that had been determined to be most-, moderately-, or non-preferred. Both positive and negative behavioral contrast occurred when the reinforcers in one component were held constant and the duration or type of reinforcer obtained in the other component varied. Undermatching occurred when the relative rate of responding during a component was plotted as a function of the relative duration of the reinforcers in that component.  相似文献   
118.
A coaching strategy to decrease errors in swimming strokes with swimmers who had not improved under "standard" coaching procedures was investigated using a multiple baseline design across subjects and swimming strokes. The procedure resulted in a large decrease in errors on swimming strokes during sessions in a training pool. Stimulus generalization of improved performance to normal practice conditions in the regular pool was observed with all but one swimmer. This improvement was maintained during two maintenance phases lasting approximately 2 weeks, as well as under standard coaching conditions during at least a 2-week follow-up. For two swimmers, error rates on one of the strokes showed a gradual increase between the third and fifth week of follow-up, but brief remedial prompting sessions immediately corrected their performance. Some beneficial response generalization to other components of the stroke being trained was observed, but no improvements were found on untrained strokes. The error correction package did not disrupt practice, require excessive amounts of the coach's time, or necessitate the use of cumbersome apparatus. In addition, the coach and the swimmers considered the procedures to be effective, and expressed their willingness to participate in them again in the future.  相似文献   
119.
Five experiments were conducted to assess the effects of several variables on the efficacy of feedback in reducing driving speed. Experiment 1 systematically varied the criterion used to define speeding, and results showed that the use of a lenient criterion (20 km/hr over the speed limit), which allowed for the posting of high percentages of drivers not speeding, was more effective in reducing speeding than the use of a stringent criterion (10 km/hr over the speed limit). In Experiment 2 an analysis revealed that posting feedback reduced speeding on a limited access highway and the effects persisted to some degree up to 6 km. Experiments 3 and 4 compared the effectiveness of an unmanned parked police vehicle (Experiment 3) and a police air patrol speeding program (Experiment 4) with the feedback sign and determined whether the presence of either of these enforcement variables could potentiate the efficacy of the sign. The results of both experiments demonstrated that although the two enforcement programs initially produced larger effects than the feedback sign, the magnitude of their effect attenuated over time. Experiment 5 compared the effectiveness of a traditional enforcement program with a warning program which included handing out a flier providing feedback on the number and types of accidents occuring on the road during the past year. This experiment demonstrated that the warning program produced a marked reduction in speeding and the traditional enforcement program did not. Furthermore, the warning program and a feedback sign together produced an even greater reduction in speeding than either alone.  相似文献   
120.
The dual purposes of applied research-contributing to understanding and improvement-are only partially served by method systems that encourage studying (with increasing precision) a narrow range of questions of modest societal importance. To optimize contributions to challenging societal problems, a field's cherished standards should be adapted to support more adventuresome forms of community research and action. This paper outlines 10 values for community research and action, based on insights from the fields of behavioral and community psychology. These values-reflect the goals and challenges of establishing collaborative relationships with research participants, determining research goals and methods, designing and disseminating interventions, communicating research findings, and advocating for community change. Critical challenges are outlined, and implications for the field and its clients are discussed.  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