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261.
This comment responds to an article by Range and Cotton (1995) on reporting of parental permission and child assent procedures in published articles for 4 psychology journals. Issue is taken with the assumptions, methodology, interpretations, and implications of listing researchers in the Range and Cotton article. There is no evidence researchers failed in their ethical obligations or that children were put at risk. Reporting permission/assent in publications is not an ethical requirement. Listing researchers as "failing" to do something not part of an ethical code is lamentable. Too many unfortunate implications and problems can be derived from Range and Cotton's analysis and conclusions.  相似文献   
262.
263.
Recent speech research has begun to evaluate the internal structure of categories. In one such study, Kuhl (1991) found that discrimination was poorer for vowel stimuli that were more representative of the category (prototype, or P, set) than it was for less representative stimuli (nonprototype, or NP, set). This finding was interpreted as indicating that a category prototype may function as a “perceptual magnet,” effectively decreasing perceptual distance, and thus discriminability, between stimuli. The present study examines the function of prototypes in a musical category—another natural, but nonspeech category. Paralleling the Kuhl study, representative (P) and less representative (NP) sets of major triad stimuli were constructed, based on equal temperament. Musically experienced subjects rated the stimuli in each set for goodness as a major triad, with the highest rated stimulus serving as a prototype standard for a subsequent discrimination task. Results from the discrimination task demonstrated better performance in the P context than in the NP context. The current nonspeech results indicate that a prototype functions as an anchor rather than a magnet. In addition to providing a natural, nonspeech standard for comparison with speech findings, the results provide some important insights into the nature of musical categories.  相似文献   
264.
A technique is described for rapidly collecting responses in auditory-localization experiments. Subjects indicate the perceived direction of the sound by pointing at a 20-cm-diam spherical model. In Experiment 1, the subjects judged the direction of a broadband signal, which could originate from any of 239 directions ranging through 360° of azimuth and between ?45° and +90° of elevation. Using this technique, the subjects responded 2–8 times more rapidly than previous subjects who used either a verbal-reporting technique or a head-pointing technique. Localization judgments were as accurate as they had been with verbal reports, but were not as accurate as judgments collected using the head-pointing technique. In Experiment 2, the signal was turned off and the experimenter read the spherical coordinates of the signal location to the subjects. The subjects pointed to these coordinates more accurately than they had judged the direction of the sounds in Experiment 1, suggesting that the response technique had not been the limiting factor in that experiment. Circumstances relevant to the choice of response techniques for auditory-localization experiments are discussed.  相似文献   
265.
Aggressivity, inattention, hyperactivity, and impulsivity are cardinal dimensions of externalizing behavior problems of childhood. They are diagnostic and clinical features of childhood disorders, and are thought to be linked to the subsequent development of adult disorders such as substance abuse (SA). Little is known, however, about the convergent and discriminant validity of these four constructs. We used multiple measures to develop indices of aggressivity, inattention, hyperactivity, and impulsivity in a sample of 10- to 12-year-old boys (N=183) with and without a family history of SA. Data were taken from mother reports, child reports, teacher reports, and laboratory tasks. The study aims were (1) to test the convergent and discriminant validity of aggressivity, inattention, hyperactivity, and impulsivity; (2) to examine whether the data were consistent with a model specifying the four constructs as indicators of one superordinate factor; and (3) to differentiate boys with and without a family history of SA in construct scores. The results supported the convergent and discriminant validity of the four constructs. Although discriminable, the constructs covaried strongly and were consistent with a model specifying them as indicators of a single superordinate factor. Boys with a family history of substance abuse scored higher than control boys on aggressivity, inattention, and impulsivity scores, but the groups did not differ on hyperactivity scores. The results are discussed in terms of the role of childhood behavior problems in vulnerability to SA.This work was supported by the National Institute on Drug Abuse grant No. DA 05605.  相似文献   
266.
The correlations and comorbidities of a series of adolescent problem behaviors were studied in a sample of 739 New Zealand 15-year-olds. This analysis revealed the presence of strong comorbidities between different problem behaviors. The data were modeled using methods of unrestricted latent class analysis and this suggested that the best fitting model to describe the data was one which assumed that adolescent problem behaviors were described by four general classes of children. While the same general four-class model applied to males and females, there were marked gender differences in the rates of problems. Specifically, the predominant problem behaviors in females were those relating to an accelerated transition to adulthood marked by early sexual activity, alcohol abuse, and cannabis use whereas the predominant problems for boys were related to antisocial and law-breaking behaviors. Rates of children with no problems (85%) and with multiple problems (3%) were similar for boys and girls.This research was funded by grants from the Health Research Council of New Zealand, the Canterbury Medical Research Foundation, and the National Child Health Research Foundation.  相似文献   
267.
268.
It is shown that J. M. Keynes was the originator of what is called a weighted monetary value (WMV) approach to decision making under uncertainty and risk as opposed to either the expected monetary value (EMV) or subjective expected utility (SEU) approaches.  相似文献   
269.
This and the following papers were presented at a symposium organized by David M. Levin honoring the work of Eugene Gendlin at meetings of the Society for Phenomenology and the Human Sciences, Boston, October, 1992.  相似文献   
270.
Monsour  Michael  Harris  Bridgid  Kurzweil  Nancy  Beard  Chris 《Sex roles》1994,31(1-2):55-77
This research was an investigation into four challenges purported to confront cross-sex friends. One hundred and thirty eight individuals (females = 86, males = 52) completed two surveys designed to explore the extent to which the sexual, emotional bond, audience, and equality challenges were present in their cross-sex friendships. Over 98% of the participants were heterosexual, 99% were Caucasian, and approximately 5% were Hispanic. Data gathered from the first survey were analyzed using a three-way analysis of variance, with gender, type of friendship, and romantic status as the independent variables, and three of the four challenges as the dependent variables. The first survey also included open-ended questions designed to explore the nature and existence of the challenges. The second survey was in a diary format. Respondents kept a frequency count for three weeks of discussions they had with their cross-sex friend concerning the challenges, and thoughts that they had as individuals concerning those challenges. Results from both surveys indicate that though the challenges exist and have powerful effects on a small percentage of individuals in cross-sex friendships, for the majority of participants the challenges are not perceived as salient.  相似文献   
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