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111.
Since baseline performance varies with age, diminished interference effects found with increasing age do not provide evidence for a developmental trend in distractibility unless their relationship to baseline performance is known. In the present study, baseline difficulty was varied in two speeded classification experiments to investigate whether interference effects due to irrelevant information could best be characterized by absolute or proportional decrement models. In Experiment 1, first graders, third graders, and adults sorted cards on the basis of square size, both in the presence and absence of extraneous stimulus information. In Experiment 2, first graders and adults sorted cards on the basis of the density of a regular array of dots and two kinds of irrelevant information were used. Robust interference effects were found which declined with age. Manipulating discriminability of the relevant stimulus dimension resulted in large changes in sorting time, but interference effects did not vary with baseline difficulty. These results were interpreted as strongly supporting both an absolute decrement model and a developmental trend in distractibility.  相似文献   
112.
A serious methodological error was committed by Stephens et al. (1972), the protestations of the present critics notwithstanding. When studying the relationship between two sets of variables, it is clearly wrong to hold chonological age constant in one set and allow it to vary in the other. This error spuriously reduces the correlation between the two sets. A demonstration that the two sets define different first-order factors provides very little information about the degree of relationship present, which must be derived from the intercorrelations of those factors. In the original research, these were also biased by the methodological error. The conclusion of Humphreys and Parsons that Piagetian tasks and intelligence tests could be used interchangeably is reinforced. The hypothesis that the relatively small amount of unique variance in the Piagetian composite is relatively unimportant psychologically can only be discarded on the basis of good empirical research, not debater's arguments.  相似文献   
113.
This study investigated the effects of presumably positive and neutral response-contingent stimuli on the occurence of stuttering. Eight adult stutterers spoke spontaneously during a 60-min experimental session, which was divided into three 20-min periods. During Condition I no stimuli were delivered. During Condition II a digital counter and a pair of yellow lights were activated each time the subject stuttered. During Condition III these same response-contingent stimuli were delivered, but with the additional factor that the subject would earn 5¢ each time the counter moved forward and the lights were illuminated. Conditions II and III were counterbalanced across subjects. The experimenter was unaware of which of the two contingencies were operative during Conditions II and III. Results showed no significant changes in occurence of stuttering due to either response-contingent stimulus. A discussion of theoretical and experimental implications is given.  相似文献   
114.
115.
Statistical significance tests are derived and evaluated for measuring apparent differences between an obtained and an expected binormal ROC curve, between two independent binormal ROC curves, and among groups of independent binormal ROC curves. A binormal ROC curve is described by two parameters which represent the spread of the means and the ratio of the standard deviations of the two underlying Gaussian decision variable distributions. To test the significance of apparent differences between or among ROC curves, approximate χ2 statistics for each of the three tests were constructed from maximum likelihood estimates of the two parameters defining the binormal ROC curve. The performance of each test statistic was evaluated by simulating five-category rating scale data with equal numbers of noise and signal-plus-noise trials (set at 50, 250, and 500) for each of three typical ROC curves. For the significance test involving only one ROC curve, rating scale data were generated from the chance diagonal of the ROC space also. Although test performance was found to be somewhat dependent on the number of trials and on the location of the ROC curve in the ROC space, comparisons of the obtained and expected fractions of (falsely) significant results at various α levels showed the proposed statistical significance tests to be reliable under practical experimental conditions.  相似文献   
116.
A random utility model of choice was developed by combining the basic ideas of the well-known theories of Thurstone and Restle. The new model has exactly the same number of free parameters as Tversky's Elimination-by-Aspects model. Furthermore, both models were found to fit, with equal accuracy, the data reported by Rumelhart and Greeno, and Tversky. It was concluded that although the two theories are not identical, they may be difficult to discriminate empirically.  相似文献   
117.
Previous results indicate that people conform more to group judgments when they have received unanimous group support for their opinions than when they have received no support. The present study tested the hypothesis that these differences would be attenuated when future interaction with the group members was anticipated. The 70 male subjects were tested in a Crutchfield-type conformity situation, where prior group support (100 vs 0%) and anticipation of future interaction (alone vs group) were manipulated. Predictions were based on an examination of conformity incentives that considered normative and informational sources of social influence, as well as Hollander's model of idiosyncracy credit. Consistent with predictions, conformity in the 0% prior support condition was greater when subjects anticipated future group interaction than when they did not, whereas the reverse was true in the 100% prior support condition. In addition, conformity was correlated negatively with both confidence in task ability and feelings of group acceptance when future interaction with the group was anticipated. These data suggest that when future group activity is expected, the tendency to reciprocate past treatment from the group is reduced.  相似文献   
118.
The effect of contextual stimuli on proactive interference in the rat was investigated in three experiments. The task was a modified delayed alternation procedure in which the rat was initially forced to one side of a T maze (the interfering forcing) followed by a forcing to the opposite side (the target forcing). A free choice run followed the target forcing in which a turn in either direction could be made. In order to obtain reinforcement on the free choice run, the rat was required to turn in the direction opposite that of the target forcing (i.e., in the same direction as the interfering forcing). Manipulation of the context prevailing during the interfering forcing, target forcing, and free choice runs revealed that free choice accuracy was (a) greater when the interfering and target forcings were conducted in different contexts than when they were conducted in the same context and (b) influenced only slightly, if at all, by whether the free choice context coincided with that prevailing during the interfering forcing or with that prevailing during the target forcing.  相似文献   
119.
Experiments 1 and 2 examined the effects of various durations of lickcontingent delays of reinforcement on the development of schedule-induced polydipsia. Food was provided every 1 min in the absence of licking. Delays of 1 min or more effectively disrupted the development of the licking behavior. In Experiments 3 and 4 a lick-contingent stimulus was provided in addition to the delay of food delivery. A light, which was turned on by a lick and turned off by food, greatly enhanced the development of polydipsia under delays that had previously prevented such development. A tone proved less effective than the light in promoting the development of polydipsia. Adventitious reinforcement and conditioned punishment explanations of these results were considered. A distinction was drawn between the mechanism responsible for the development of schedule-induced behavior and that responsible for its maintenance.  相似文献   
120.
The long-term effects of infantile malnutrition on information processing were studied in squirrel monkeys. From 2 through 8 weeks of age, four low-calorie infants were fed reduced amounts of a high protein diet, limiting their mean body weight gain to 23% of that of four well-fed controls, with all of this gain occurring during the first 2 weeks on the low-calorie diet. Thereafter, both groups received the standard diet ad libitum. At 68 weeks of age, incidental learning was tested by introducing shape cues that were redundant to the solution of a previously learned, two-choice, color discrimination. Removal of the color cues showed that the low-calorie monkeys had learned significantly less about the shape cues than had the controls. The basis for this incidental learning failure was then examined with an embedded-figures dicrimination, to measure attentional ability, and a novel stimulus substitution task, to measure curiosity. The groups did not differ in detecting embedded figures, but the low-calorie monkeys were significantly less likely than controls to select or handle novel stimuli that had been substituted for previously learned discriminative cues. It was concluded that undernutrition in infancy may induce a long-term strategy of only learning information which leads to an immediate reward, while suppressing the acquisition of information due to intrinsic curiosity.  相似文献   
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