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261.
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   
262.
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   
263.
264.
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   
265.
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   
266.
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   
267.
Researchers investigated the relationship between measures of interpersonal behavior and narcissism. Eight octant measures of interpersonal behavior were constructed, and validity and reliability estimates were obtained. High school and junior high school students (N = 333) completed five measures of narcissistic vulnerability, eight octant measures of interpersonal behavior, and a measure of social desirability. Canonical correlational analysis indicated a specific pattern of interpersonal behaviors for individuals with differing levels and types of narcissistic vulnerability. A multivariate analysis of variance (MANOVA) indicated that scores on several of the scales were found to differ significantly by sex and by treatment for emotional, behavioral, or educational difficulties. Implications for counseling are considered.  相似文献   
268.
As a field of study, “research utilization” is at a turning point. Despite an accumulation of replicable findings, robust constructs, even a “soft technology” for bridging the gap between theory and practice, we are still largely in the situation of the distance between social problems of, let us say, conflict or inequality and the ability of social science to provide credible, reliable and usable solutions. At the same time, the initial paradigms, suffering from hyperrationalism, have given way to more transactional ones, and have been shaken by the tenets of postmodernism. Shaken, but not undone, as “middle-level” constructs emerge, ones that appear to link the research community with a variety of professional communities in more meaningful and durable ways. Michael Huberman has been Visiting Professor of Education at Harvard University since 1991, where he teaches research methodologies and conducts research on knowledge dissemination. He is also Senior Research Associate at the Network, Inc.  相似文献   
269.
Bravais (1850/1949) demonstrated that there are five types of periodic dot patterns (or lattices): oblique, rectangular, centered rectangular, square, and hexagonal. Gestalt psychologists studied grouping by proximity in rectangular and square dot patterns. In the first part of the present paper, I (1) describe the geometry of the five types of lattices, and (2) explain why, for the study of perception, centered rectangular lattices must be divided into two classes (centered rectangular andrhombic). I also show how all lattices can be located in a two-dimensional space. In the second part of the paper, I show how the geometry of these lattices determines their grouping and their multistability. I introduce the notion ofdegree of instability and explain how to order lattices from most stable to least stable (hexagonal). In the third part of the paper, I explore the effect of replacing the dots in a lattice with less symmetric motifs, thus creating wallpaper patterns. When a dot pattern is turned into a wallpaper pattern, its perceptual organization can be altered radically, overcoming grouping by proximity. I conclude the paper with an introduction to the implications of motif selection and placement for the perception of the ensuing patterns.  相似文献   
270.
Empirical and conceptual developments that led to the formulation of a behavior system for the sexual conditioning of male Japanese quail are described. Initial efforts concentrated on conditioning with localized conditioned stimuli and on identifying behavioral indices of conditioning. Later, learning about species-typical cues and about contextual cues was also explored, and it became evident that different types of cues control different aspects of sexual behavior. The results were used to formulate a behavior system containing both response and stimulus dimensions. In this system, contextual cues and local cues are assumed to elicit only general search behavior unconditionally. In contrast, unconditioned responses to species-typical cues of a female quail include general search, focal search, and copulatory behavior. General search, focal search, and copulatory behavior can become conditioned to local cues. Conditioning can also modify focal search behavior elicited by species-typical cues and can result in various modulatory influences between different types of stimuli. The behavior system approach provides a framework for organizing the diverse sexual conditioning effects and suggests future directions for investigation.  相似文献   
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