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141.
In some recent papers, the authors and Peter Gärdenfors have defined and studied two different kinds of formal operation, conceived as possible representations of the intuitive process of contracting a theory to eliminate a proposition. These are partial meet contraction (including as limiting cases full meet contraction and maxichoice contraction) and safe contraction. It is known, via the representation theorem for the former, that every safe contraction operation over a theory is a partial meet contraction over that theory. The purpose of the present paper is to study the relationship more finely, by seeking an explicit map between the component orderings involved in each of the two kinds of contraction. It is shown that at least in the finite case a suitable map exists, with the consequence that the relational, transitively relational, and antisymmetrically relational partial meet contraction functions form identifiable subclasses of the safe contraction functions, over any theory finite modulo logical equivalence. In the process of constructing the map, as the composition of four simple transformations, mediating notions of bottom and top contraction are introduced. The study of the infinite case remains open.  相似文献   
142.
A number of models for categorical item response data have been proposed in recent years. The models appear to be quite different. However, they may usefully be organized as members of only three distinct classes, within which the models are distinguished only by assumptions and constraints on their parameters. “Difference models” are appropriate for ordered responses, “divide-by-total” models may be used for either ordered or nominal responses, and “left-side added” models are used for multiple-choice responses with guessing. The details of the taxonomy and the models are described in this paper. The present study was supported in part by two postdoctoral fellowships awarded to Lynne Steinberg: an Educational Testing Service Postdoctoral Fellowship at ETS, Princeton, NJ and an NIMH Individual National Research Service Award at Stanford University, Stanford, CA. Helpful comments by the editor and three anonymous reviewers are gratefully acknowledged.  相似文献   
143.
Mothers' and fathers' responses on the Personality Inventory for Children (PIC) were compared for 360 clinic-referred children and adolescents. Interparent agreement was measured by several different indices. Correlations between parental pairs of scale T-scores derived from each parent averaged .66 for 13 of the profile scales; 9 of the scales exceeded this value. In contrast, mothers and fathers agreed in the classification of the presence of clinical significance an average of 77% of the time across these 13 scales, and pairs of parental PIC profiles contained an average of 3 scales in disagreement. The type of index used to measure interparent agreement was found to affect the results. The discussion examines the nature of interparent disagreement and addresses the implications regarding the use of fathers as informants on this instrument.This article is based on Thomas A. Hulbert's master's thesis. The authors extend their appreciation to James Orisell and Dena Mussaff for their assistance in data preparation and analysis.  相似文献   
144.
A variety of studies withhabitual users of nicotine, caffeine, cocaine, and amphetamines have shown that administration of these stimulants has the paradoxical effect of lowering arousal states. Research on transmarginal inhibition shows that when subjects are presented with a succession of stimuli monotonically increasing in intensity, GSR and related arousal responses increase first and then begin to decline beyond a certain point of stimulus intensity. That is, following repeated exposure to intense stimuli, continued more intense stimulation has the effect of lowering arousal. Since stimulants subjectively heighten stimulus intensity, the transmarginal inhibition data provide a basis for explaining opposing effects of stimulants on arousal, depending on dose and frequency of use. It was hypothesized that when dose levels are low and usage is infrequent, arousal increases with stimulant intake. In contrast, when dose levels are high and frequent, arousal shows decrements with new intakes of stimulant. A new questionnaire measure of characteristic arousal was developed and correlated with subjects' reports of habitual levels of stimulant and sedative intake. Weekly total stimulant use correlated significantly and negatively with characteristic arousal level, providing support for the hypothesis. This lowered arousal of frequent stimulant users was not a confound of, or due to, concomitant frequent sedative use, since total stimulant and sedative use levels were uncorrelated.The author would like to thank Janice Schafrik for running the subjects in this study.  相似文献   
145.
Psychopathology and symptom patterns were studied in 60 former prisoners-of-war (POWs) by administering standardized tests including the Minnesota Multiphasic Personality Inventory (MMPI), an adjustment problem checklist, and a structured clinical interview. Most POWs showed marked psychological impairment, but modal profile analysis identified two prototypic MMPI patterns, which differed in pervasiveness and type of psychopathology. Profile subtypes were defined by unique clusters of clinical symptoms and differed in confinement stress severity. The typology of symptoms argues against a homogeneous conceptualization of stress-induced disorders and suggests the need for definition of the severity and subtype of stress phenomena and individual difference factors in responding to trauma.  相似文献   
146.
The need to train accurate, not necessarily agreeing, observers is discussed. Intraobserver consistency as an intermediate criterion in such training is proposed and contrasted with the more familiar criterion of interobserver agreement. Videotaped observations of social interactions between handicapped and nonhandicapped preschoolers provided the medium for examining the criterion agreement of four observers trained against each type of standard. Observers generally failed to show high levels of criterion agreement whether trained to a within- or to a between-observer agreement standard. The results varied somewhat with the frequency of behaviors, however. Correlations between interobserver agreement and intraobserver consistency were variable but somewhat higher when interobserver agreement was the training criterion than when intraobserver consistency was the criterion. Correlations between interobserver agreement and criterion agreement ranged from — .16 to .89 during interobserver agreement training. Correlations between intraobserver consistency and criterion agreement ranged from — .23 to .99 during intraobserver consistency training.  相似文献   
147.
This study examined whether norms that concerning assisting frail older parents were different for daughters than for sons when the adult children are members of dual-earner couples. Data were gathered by telephone interviews from a probability sample of 315 adults residing in western Alabama. Of the 18 statements presented, statistically significant differences between the expectations for daughters and sons occurred in only three cases (help with housework, meal preparation, and yard work), suggesting substantial support for norms of equalitarianism. Further, there were few differences between the expectations held by females and by males for daughters and sons. Generally, the results suggested strong support for behaviors that facilitate the independent living of both adult children and their frail older parents.The authors acknowledge with thanks the assistance of the University of Alabama's Capstone Poll, which collected the data for this study.  相似文献   
148.
The deleterious effects of occupational stress on worker health and well-being have been described in numerous reports for a wide range of work groups. Work overload (and underload), deadline pressures, role Stressors, underutilization of abilities, and physical discomfort have been identified as work factors associated with increased stress symptom reporting. The relationship between work stress and accident/injury occurrences is less clearly documented, although scattered reports in the literature suggest a contributory role for stress in the accident process. In this article, data linking stress to unsafe work behavior are reviewed and a model is proposed wherein accidents can arise from impaired worker capabilities (e.g., slower reaction time) brought about by stress symptom activity (e.g., anxiety). The potential usefulness of stress management training (SMT) for shortcircuiting the stress/accidents cycle by alleviating stress symptoms is discussed in light of recent empirical research.Portions of this article were presented at the Third Annual Scientist/Practitioner Conference in Industrial/Organizational Psychology, Virginia Beach, Virginia, October, 1982.  相似文献   
149.
Integration is one of the most prevalent contemporary themes in the field of family therapy. This discussion proposes a process-based model of integration which transcends theoretical content. A brief review of integrative efforts in the field of marriage and family therapy is followed by an exploration of issues related to theoretical content. A model for understanding the personal process of integration is developed which articulates a five stage process of integration. Finally, after a brief character development to illustrate the different stages, some initial implications for a process-based model of integration are explored.David J. Moultrup, MSW, LICSW, is in private practice in Arlington, Massachusetts.  相似文献   
150.
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