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101.
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   
102.
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   
103.
The purpose of this study was to compare a non-clinic sample of mothers and children to two groups of clinic-referred children and their mothers. The two clinic-referred groups differed from one another in that the selection criterion for one group of children (Clinic Deviant) was that they were significantly more deviant and non-compliant than the non-clinic group whereas the selection criterion for the second group of children (Clinic Non-deviant) was that they did not differ significantly from the non-clinic group on deviant and non-compliant behavior. Home observations by independent observers and parent questionnaires examining parental adjustment and parental perceptions of child adjustment were completed. The results indicated that both clinic groups perceived their children as more maladjusted than parents in the non-clinic groups perceived their children. Parents of the children in the Clinic Non-deviant group were significantly more depressed than those in the remaining two groups, whereas parents in the Clinic Deviant group issued more vague, interrupted commands than those in the Clinic Non-deviant group. Implications of the findings are discussed.  相似文献   
104.
Behavioral interventions for primary dysmenorrhea are reviewed under four categories: hypnotherapy; Lamaze exercises; biofeedback training; and desensi found in only the last category and even here, the extent to which positive results stem from desensitization-based treatments themselves as opposed to nonspecific factors associated with these treatments is unresolved. Additional issues that bear upon behavioral treatments for primary dysmenorrhea are: (a) the need for further taxonomic refinement; and (b) the need to incorporate pathophysiological findings within the treatment of this disorder.  相似文献   
105.
In 14 experiments, subjects had to “point to” surrounding environmental locations (targets) while imagining themselves in a particular spot facing in various directions (orientations). The spatial information was either committed to memory (cognitive maps) or directly presented on each trial in the visual or tactile modality. Reaction times (RT) indicated that orientation shifts were achieved through mental rotation in the visual task, but not in the cognitive map or tactile tasks. Further, in the latter two tasks targets were located most quickly when they were adjacent to or opposite the imagined orientation. Several explanations of this finding were tested. Various aspects of the data suggest that cognitive maps are not strictly holistic, but consist of orientation-specific representations, and—at least in part—of relational propositions specific to object pairs.  相似文献   
106.
A family approach using the techniques of behaviour modification, to a family presenting with problems of encopressis in a five-year-old boy, is described. The usefulness of taking a broader analysis of the context of the behaviours targeted for modification under the impact of systems theories is emphasized. A one-year follow-up after treatment demonstrated both symptomatic and family changes.  相似文献   
107.
This study examined the location and rate of stuttering in the spontaneous speech of nine young stutterers (4.0–6.6 yr) in relation to certain aspects of syntax. It was designed to answer the following questions: Is there more stuttering at clause onset (boundary) than at other points in the clause? Does the type of clause influence rate of stuttering? Is there more stuttering on complex than on simple sentences? The syntactic analysis defined 10 clause types (seven pertaining to complex sentences and three pertaining to simple sentences); clause boundaries (taking into account “filler” words occuring in such positions); and hierarchical constituent structure within sentences. Stuttering was found with significantly greater frequency at clause boundaries than at internal (nonboundary) positions of clauses. This was apparent for nine of the 10 clause types, the exception being complement clauses. The word “and” at the beginning of simple and complex sentences provoked a high rate of stuttering. The hierarchical structure within the clause did not influence the location of stuttering, and sentence complexity was not a factor in the rate of stuttering.  相似文献   
108.
Psychological studies of masculinity-femininity in children have paralleled those done with adults, which often consider deviations from masculinity for males and femininity for females as abnormal and perhaps pathological. Children who demonstrate cross-sex behaviors, however, may become androgynous adults whose cross-sex behaviors mean flexibility, not pathology. This study had two purposes: (1) to identify potentially androgynous children as those labeled by their peers as tomboys and sissies; (2) to compare personality characteristics of androgynous children with those of peers. Subjects were 312 elementary school children in a midwestern city. Results indicate that the labels tomboy and sissy are not necessarily indicators of androgynous children, but important social behaviors are related to the labels. For males, the possibility of frustrated creativity was raised.  相似文献   
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