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981.
In a series of three experiments, subjects made risky decisions under conditions of hypothetical or real consequences. Task variations across experiments included: (1) type of risk (monetary gambles or investments of time and effort), (2) within-subject and between-subjects manipulations of consequence condition, and (3) single or multiple decisions. The hypothesis of no difference between choices in real and hypothetical consequence conditions was retained in each experiment. Supplemental analyses ruled out various “artifactual” interpretations of the null results. Discussion focused on conditions in which researchers can and cannot infer decision makers’ actual risk preferences from their responses in laboratory tasks.  相似文献   
982.
This article presents an approach we have developed for the assessment of public research institutions in the natural sciences and engineering. The method consists in the exploitation of available S&T databases and indicators, including bibliometrics (databases of scientific as well as technical literature), patents, and internal data. Results are therefore derived through multiple databases. The objective is to profile a specific national R&D community in order to assess the positioning of a public institution or program within the community to which it belongs. It involves obtaining the profile of the evolution of an R&D area, the R&D performers, the financing and support institutions, the users of R&D results, and the interactions between all these actors. A case-study of Canadian research in polymers is presented. Part of this research was financed by the National Research Council of Canada, and by a strategic grant from the Social Sciences and Humanities Research Council. The research benefited from the expertise of Robert Letellier, Robert H. Marchessault, Jacques Martel, and Marielle Piché, and from the technical assistance of Maryse Prud’homme, Marcel Parent, and Benoit Longpré.  相似文献   
983.
The National Conference of Catholic Bishops has argued for significant government involvement in health care in order to assure respect for what they regard as the right to health care. Critics charge that the bishops are wrong because health care is not a right. In this article, it is argued that these critics are correct in their claim that health care is not a right. However, it is also argued that the premise that health care is not a right does not imply that the market is the most equitable and just system for providing health care. Natural law arguments in the tradition of Roman Catholic social teaching lead to the conclusion that a just and prosperous society has a moral obligation to provide health care even if there is no such right. Further, there are strong moral grounds for concluding that the bishops are correct in their claim that health care ought not to be considered a market commodity. It is argued that if health care ought not to be considered a commodity, then national health insurance is the best available alternative for fulfilling the social obligation to distribute health care resources justly and fairly at this time in American history. The bishops' case for government involvement can be made on the strength of the Catholic tradition in theological argumentation, independent of the claim that health care is a right.  相似文献   
984.
College students periodically experience many challenges in pursuit of their educational goals. Such experiences can have deleterious effects on subsequent motivation and performance when they are perceived as negative. Research shows that some students who experience negative events are buffered against motivational deficits, whereas others are motivationally at-risk. Several individual difference variables have been proposed to account for such diverse reactions. A longitudinal field study that involved three phases was conducted to extend this research. Phase I examined the motivational buffering effects of academic attributional style on students' performance, motivation, and emotions. Results indicated that attributional style related to students' performance, motivation, and emotions. Specifically, students who routinely made unstable and controllable attributions for negative academic events exhibited the greatest performance and motivation compared to students who typically made stable and uncontrollable attributions. Phases II and III were designed to examine the remedial benefits of attributional retraining for different attributional styles. Findings indicated that attributional retraining influenced motivation, emotions, and course grade. These results were qualified by the interaction between attributional style, attributional retraining, and time. Findings are discussed within Weiner's (1985, 1986) attribution theory. This research was based, in part, on the first author's dissertation submitted to the Department of Psychology and the Faculty of Graduate Studies of The University of Manitoba in partial fulfillment for the Degree of Doctor of Philosophy. This research was supported by a Social Sciences and Humanities Research Council of Canada (SSHRCC) doctoral fellowship, a University of Manitoba doctoral fellowship, and a SSHRCC postdoctoral fellowship to the first author. In addition, the research was also supported by a SSHRCC research grant (#410911296) to the second author. The authors gratefully acknowledge the helpful comments of Bernard Weiner, Harvey Keselman, John Adair, Rodney Clifton, and Robert Altemeyer. Also appreciated was the assistance of Verena Menec and the Higher Education Research group.  相似文献   
985.
The purpose of the present research was to propose and test a motivational process model of academic achievement. The model posits that parental, teachers, and school administration support for students' autonomy positively influences students' perceived school competence and autonomy. In turn, perceived school competence and autonomy affect positively self-determined school motivation which in turn influences academic achievement. Two studies using a prospective design tested the adequacy of the model. In Study I, participants were 1,623 ninth-grade students. Results from structural equation modeling supported the motivational model. Participants in Study 2 were 1,098 tenth-grade students. Results from this study corroborated those of Study 1 controlling for students' prior achievement in the ninth grade. The role of self-determinod school motivation in academic achievement is discussed and avenues for future research are considered. This research is part of a larger project that is being funded by grants from the William and Flora Hewlett Foundation; the San Francisco Foundation; the Robert Wood Johnson Foundation; the Danforth Foundation; the Smart Foundations; the Pew Charitable Trusts; the John D. and Catherine T. MacArthur Foundation; the Annenberg Foundation; Spunk Fund, Inc.; the DeWitt Wallace-Reader's Digest Fund, Inc.; Louise and Claude Rosenberg; and the Center for Substance Abuse Prevention, U.S. Department of Health and Human Services. The views expressed in the paper are those of the authors and not necessarily of the funders. We are grateful to the many educators, students, and colleagues who cooperated with us on this project and to several anonymous reviewers who provided helpful suggestions.  相似文献   
986.
An injection olfactometer for human psychophysical experiments is described. The olfactometer is capable of presenting, either mono- or birhinally, single odorants and binary mixtures. The pulse form of the olfactory stimulus at the exit of the olfactometer approaches a rectangular form, which makes the olfactometer well suited for olfactory reaction time measurements. Since stimulation periods are independent of the subject’s inhalation, time-intensity measurements over prolonged periods of time are possible as well. In the second part of this paper, a new technique is described for the measurement of the stimulus pulse form at the exit of the olfactometer.  相似文献   
987.
We investigated the ability of subjects to discriminate sugars with a whole-mouth forced-choice paradigm, in which a standard solution was compared with a test solution of varied concentration. Discrimination probabilities were U-shaped functions of test concentration: for 6 subjects and pairwise combinations of fructose, glucose, and sucrose, discriminability always declined to chance over a narrow range of test concentrations. At concentrations ≦ 100 mM, maltose was indiscriminable from fructose but discriminable at higher concentrations for 4 subjects. By analogy with themonochromacy of night vision, whereby any two lights are indiscriminable when their relative intensities are suitably adjusted, we call the gustatory indiscriminability of these sugarsmonogeusia. The simplest account of monogeusia is that all information about the indiscriminable sugars is represented by a single neural signal that varies only in magnitude. The discriminability of maltose from the other sugars at higher concentrations is consistent with the hypothesis that maltose also activates a second gustatory code.  相似文献   
988.
During linear translation through a stationary environment, the pattern of optical flow generated on each retina is symmetrical when the head is aligned with the heading, but during lateral gaze the optical flow is asymmetric. We assessed whether human subjects could use the magnitude of this asymmetry to determine the direction of heading during passive translation through a 3-D environment. When allowed to move their heads in order to look in the direction of self-motion, subjects indicated their heading precisely and accurately. When the head was locked in alignment with the misaligned body, and gaze adjustments were not allowed, responses were quite precise, but showed a large bias which increased with increasing heading angle.  相似文献   
989.
Koss  Mary P.  Leonard  Kenneth E.  Beezley  Dana A.  Oros  Cheryl J. 《Sex roles》1985,12(9-10):981-992
Sex Roles - Rape is an underreported and underconvicted crime. Therefore, many highly sexually aggressive men are missed by research employing judicial identification for sample selection. The...  相似文献   
990.
The purpose of this paper is to review the necessary components of a comprehensive group therapy program. The balancing between the didactic and the experiential portions, and an analysis of the selection criteria, along with the rationale for a particular sequencing of elements in the curriculum, are discussed. A line between supervision and personal therapy is drawn. The author describes the milieu necessary for a successful training program to evolve and makes suggestions for improvements. The various experiential aspects of training are presented and critically evaluated. The training situation is examined from the point of view of the faculty, the trainee and the patients involved. The author marshalls evidence indicating that personal group psychotherapy in a patient group is the preferred form for most trainees for the experiential part of the program. The paper concludes that the sharing and cohesiveness of training philosophies and methods by the faculty is a prerequisite to the success of any training program.  相似文献   
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