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931.
Performance on associated mixed and multiple variable-interval-extinction schedules was studied as a function of food versus intracranial stimulation (ICS) reinforcement. For the mixed schedule, differential responding was greater for an ICS reinforcement group than for a food reinforcement group, demonstrating that conditions affecting resistance to extinction help to determine the control exerted by a mixed schedule. Performance on the multiple schedule demonstrated greater differential responding for an ICS group than for a food reinforcement group during the early training sessions, indicating that the control exerted by mixed schedules interacts with that exerted by the exteroceptive discriminative stimuli. The results suggest that the influence of the associated mixed schedule on discriminative responding would be greater, the greater the difficulty of the stimulus discrimination.  相似文献   
932.
Reinforcement of eye movement with concurrent schedules   总被引:7,自引:7,他引:0       下载免费PDF全文
Human macrosaccadic eye movements to two areas of a four-dial display were conditioned by concurrent variable-interval schedules of signals. Reinforcers (signals) were delivered to the two right-hand dials on one schedule and to the two left-hand dials on another, independent schedule. The use of a changeover delay between crossover eye movements and reinforcement had the effect of changing the pattern of scanning from fixating four dials in succession or in a Z-shaped pattern to scanning vertically the dials on either side with fewer crossovers. In the presence of a changeover delay, subjects matched relative eye-movement rates and relative reinforcement rates on each schedule. Rate of crossover eye movements, with a changeover delay in effect, was also inversely related to the difference in reinforcements arranged by the concurrent schedules. The results suggest that for stimuli whose critical components are arranged spatially, conditioned eye movements play an important part in selective stimulus control.  相似文献   
933.
Ss were asked to indicate points 1 week, 7 months, 3 years, and 9 years in the past and future on two time lines representing birth to present and present to death. Data for 90 college-age Ss fit a psychophysical power function following Stevens’s law. with negatively accelerated growth indicating proportionately greater linear representation of periods nearer to the present. Variability was greater for the representations of the future than of the past, with monotonic increases in variability as distance from the present increased.  相似文献   
934.
The purpose of this study was to document the relationship of parents' personal and marital adjustment to their own behavior as parents and the behavior of their children. A total of 31 families who had been referred for behavioral counseling regarding their male child's behavior problems were given a diagnostic battery which included home observations as well as administration to parents of the Minnesota Multiphasic Personality Inventory (MMPI) and the LockeWallace Marital Adjustment Test. Results revealed consistent negative relationships between marital satisfaction and the observed level of child deviance. Similarly, there were consistent negative relationships between marital satisfaction and the level of observed “negativeness” to the child. Analyses using the MMPI indicated that a large number of the fathers ' MMPI scales were related to child deviance, but this finding was not replicated for mothers. Several MMPI scales were related to marital satisfaction for both parents. These results are discussed in terms of their implications for the assessment and treatment of families with a problem child.  相似文献   
935.
Memory for schematic faces was studied using a recognition memory paradigm. Ss indicated whether two faces, separated by delays of 6, 12, or 18 sec, were the same or different. Theoretical interest centered on the effects of component feature saliency on response bias and detectability. The main results were that there were fewer misses and more false alarms on the more salient features. Analysis showed that the main effect of feature saliency was on response bias, not detectability.  相似文献   
936.
Investigation of psychopathology in monkeys requires analysis of multiple variables mediating specific behaviors. Assessment of both the relative contribution of each variable and the interactions among them is facilitated by the use of apparatuses whose designs permit separate or simultaneous manipulation of several variables. Three such devices, the pit, the tunnel of terror, and the standard living-experimental cage, each specifically constructed for the production of depression or despair in monkeys, are described.  相似文献   
937.
Two tasks. using identical geometric forms. compared nasal peripheral. temporal peripheral. and central viewing. In the first task. using a yes-no confidence rating scale procedure, four Ss judged the presence or absence of a known geometric form (detection). In the second task. the same Ss judged which of several know forms was presented (identification). The major result is that nasal and temporal peripheral viewing are similar and that both peripheral regions differ from central viewing. Also, detection and identification are relatively independent processes; the ease of detection of a form does not predict the ease of identification of that form.  相似文献   
938.
Hierarchical clustering schemes   总被引:74,自引:0,他引:74  
Techniques for partitioning objects into optimally homogeneous groups on the basis of empirical measures of similarity among those objects have received increasing attention in several different fields. This paper develops a useful correspondence between any hierarchical system of such clusters, and a particular type of distance measure. The correspondence gives rise to two methods of clustering that are computationally rapid and invariant under monotonic transformations of the data. In an explicitly defined sense, one method forms clusters that are optimally connected, while the other forms clusters that are optimally compact.I am indebted to R. N. Shepard and J. D. Carroll for many stimulating discussions about this work, and for aid in preparing this paper.  相似文献   
939.
Tactile pattern recognition was studied by presenting pairs of alphabetic shapes in rapid succession at the same anatomical location, the subject being required on each trial to identify bath of the patterns. Experimental variables were the duration of each stimulus and the time between stimuli. Three aspects of the observed interaction were (1) an increase in letter reversals for very short interstimulus intervals; (2) a greater percentage of first-response errors for short-stimulus onset intervals and a greater percentage of second-response errors for long-stimulus onset intervals; and (3) a crossover in the first- and second-response error rates in the range of 100 to 200 msec. after the onset of the first stimulus. These results are consistent with some of the temporal properties of models proposed for analogous visual tasks.  相似文献   
940.
Evidence of hierarchies in cognitive maps   总被引:17,自引:0,他引:17  
Previous research suggested that the apparent hierarchical organization of landmarks in an environment will influence subjects’ judgments about spatial characteristics of that environment. We extended this previous work to a natural environment that has no predetermined, well-defined hierarchical structure. Using an algorithm that generates a hierarchy of landmarks from recall protocols, we constructed hypothesized clusterings of landmarks for a set of subjects familiar with the space. Then we tested these hypothesized clusters in a series of tasks, all of which required judgments about distances in the space. The results of these tests suggest that subjects do cluster landmarks on the basis of nonspatial attributes, and that the clusters have consequences for performance in various tasks that require access to spatial information.  相似文献   
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