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991.
Incest is a major mental health problem, in terms of both prevalence and morbidity. Father-daughter incest constitutes the majority of reported cases. The possibility of incest should be considered in a family which includes a violent father, a disabled mother, a child in an adult maternal role, or an acting out adolescent girl. Intervention requires recognition of the criminal and addictive aspects of the father's behavior. Active cooperation between mental health professionals and mandated child protective and law enforcement agencies is necessary for effective treatment. Group therapy and affiliated self-help programs appear to be the treatment modality of choice. Rehabilitation of the family is based upon restoration of the mother-daughter bond as a guarantee of safety for the child.  相似文献   
992.
Many basic psychophysical functions offer promise as clinical tests of vision. Here, we discuss problems that one encounters in the clinical setting, how one identifies a psychophysical test for potential clinical development, and an orderly approach to development of suitable test paradigms. Parameters are selected which are relatively insensitive to variables encountered in the field (clinic) in a normal population, but which are sensitive to changes in the response system being studied. Initial data on two hyperacuity tests are presented. These tests are adaptations of hyperacuity paradigms (Westheimer, 1979) to a clinical environment. This particular test set offers promise because it exhibits a unique threshold which is dependent upon neural data processing and is relatively independent of retinal image degradation.  相似文献   
993.
Choice reaction latencies were measured at three different a priori probabilities for two stimulus alternatives. Unlike the results of some other studies, the mean latency of a given response was nearly the same whether the response was correct or incorrect. The discriminable stimuli were a 1000- or a 1700-Hz tone presented at 70 dB SPL. Latencies and standard deviations, based on about 17,000 observations, are reported for three observers. The data are compared with predictions of the optimum sequential model of Wald and Stone and two modifications of that random-walk model, one proposed by Link and Heath and the other proposed by Laming. Fast-guess analyses were also carried out. The three-parameter version of either the sequential or the modified random-walk models provided reasonably accurate predictions of the mean data for each observer. The parameters estimated by the fast-guess analysis were unrealistic. There are three obvious differences between this experiment and most previous choice reaction-time experiments. First is stimulus modality#x2014;we used an auditory signal, whereas most of the previous studies used a visual signal. Second, the observers practiced more in this experiment than in most previous experiments. Finally, there was a random foreperiod with a heavy penalty for anticipations. One or more of these factors is the probable reason for the discrepancy between our results and those of previous studies.  相似文献   
994.
995.
Interpretations regarding the effects of exogenous and endogenous variables on endogenous variables in linear structural equation systems depend upon the convergence of a matrix power series. Convergence depends upon the eigenvalues of the structural coefficient matrix. The test for convergence developed by Jöreskog and Sörbom is shown to be only sufficient, not necessary and sufficient.  相似文献   
996.
Kristof has derived a theorem on the maximum and minimum of the trace of matrix products of the form \(X_1 \hat \Gamma _1 X_2 \hat \Gamma _2 \cdots X_n \hat \Gamma _n\) where the matrices \(\hat \Gamma _i\) are diagonal and fixed and theX i vary unrestrictedly and independently over the set of orthonormal matrices. The theorem is a useful tool in deriving maxima and minima of matrix trace functions subject to orthogonality constraints. The present paper contains a generalization of Kristof's theorem to the case where theX i are merely required to be submatrices of orthonormal matrices and to have a specified maximum rank. The generalized theorem contains the Schwarz inequality as a special case. Various examples from the psychometric literature, illustrating the practical use of the generalized theorem, are discussed.  相似文献   
997.
According to frequency theories of concept attainment, acquisition of rule-governed concepts depends on discriminating relevant from irrelevant stimulus features on the basis of their respective frequencies of occurrence. Depending on the theorist, the critical frequency counts may be based on occurrence in all stimuli or on occurrence in positive instances only. Experiment 1 held frequency in positive instances constant and varied the frequency of irrelevant features in the negative category. High frequency was associated with impaired performance, but only when concept problems started with a negative instance. Experiment 2 demonstrated that some previous findings in the literature that were thought to support frequency theory also depended on problems starting with a negative instance. These findings are not easily reconciled with existing frequency theories. We attribute our results to high intercategory similarity, which is a correlate of high frequency of irrelevant features. In the context of a hypothesis-testing theory, we propose that a negative start stimulus proactively interferes with memory for information in the initial positive instance and that the extent of the interference depends on how similar negative instances are to positive instances.  相似文献   
998.
Two studies were conducted to explore the role of social intimacy in predicting the individual's response to stress. In the first study the experimenter reinforced the experimental subjects' verbalizations during an interview on a fixed schedule for the first 3 minutes, withdrawing reinforcement for the final 4 minutes. The control group received reinforcement on a fixed schedule for the total 7 minutes. Subjects scoring low on a measure of intimacy disclosed less personal material during the withdrawal period in the experimental condition than in the control condition in contrast to high scoring subjects who maintained their level of disclosure for both parts of the interview. In the second study, previously experienced life change events were assessed. Individuals lacking a current intimacy were found to be prone to higher levels of emotional disturbance especially when many previous negative or few positive life change events had occurred.  相似文献   
999.
Auditory and visual stimulus-seeking behavior was measured in hyperactive and nonhyperactive youngsters. The design controlled for motor activity level. The results indicate that hyperactive children preferred auditory stimulation more than the control children. There were no differences in stimulus-seeking preferences in the visual modality. The groups did not differ in motor activity. It was concluded that abnormally high needs for stimulation are important in hyperactivity.The authors would like to express their appreciation to James Fogarty, Superintendent, Walter Galvin, Principal, and the many teachers, students, and parents of the Greene Avenue Learning Center of BOCES II in Sayville, New York for their cooperation and support in this study. We would also like to thank Susan O'Leary, Ph.D. Director of the Point of Woods Laboratory School and the students and parents for participation and support in this study.  相似文献   
1000.
Thirty-two children aged 8–9 and 10–11 were asked to perform two statement verification tasks. Task 1 consisted of statements that were likely to elicit an affirmative knowledge representation,You have three eyes, is likely to elicit the representation,I have two eyes. Task 2 consisted of statements that were likely to elicit a negative knowledge of representation,You have a tail, is likely to elicit a negative representation,I do not have a tail. All statements varied in two dimensions, polarity (affirmative vs. negative) and truth value (true vs. false). Negative statements in Task 1 were found to be more difficult for children to verify than those in Task 2. This performance difference was used to infer the form of knowledge representation generated in verifying negative statements.  相似文献   
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