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991.
The role of contingency awareness in classical conditioning experiments using human subjects is currently under debate. This study took a novel approach to manipulating contingency awareness in a differential Pavlovian conditioning paradigm. Complex sine wave gratings were used as visual conditional stimuli (CS). By manipulating the fundamental spatial frequency of the displays, we were able to construct pairs of stimuli that varied in discriminability. One group of subjects was given an "easy" discrimination, and another was exposed to a "difficult" CS+ and CS-. A 3rd group was exposed to a stimulus that was paired with the unconditional stimulus (UCS) 50% of the time and served as a control. Skin conductance response (SCR) and continuous UCS expectancy data were measured concurrently throughout the experiment. Differential UCS expectancy was found only in the easy discrimination group. Differential SCRs were found in the easy discrimination group as well as in the difficult discrimination group, but not in the 50% contingency control. The difficult discrimination group did not exhibit differential UCS expectancy but did show clear differential SCR. These observations support a dual process interpretation of classical conditioning whereby conditioning on an implicit level can occur without explicit knowledge about the contingencies. The role of contingency awareness in classical conditioning experiments using human subjects is currently under debate. This study took a novel approach to manipulating contingency awareness in a differential Pavlovian conditioning paradigm. Complex sine wave gratings were used as visual conditional stimuli (CS). By manipulating the fundamental spatial frequency of the displays, we were able to construct pairs of stimuli that varied in discriminability. One group of subjects was given an "easy" discrimination, and another was exposed to a "difficult" CS+ and CS-. A 3rd group was exposed to a stimulus that was paired with the unconditional stimulus (UCS) 50% of the time and served as a control. Skin conductance response (SCR) and continuous UCS expectancy data were measured concurrently throughout the experiment. Differential UCS expectancy was found only in the easy discrimination group. Differential SCRs were found in the easy discrimination group as well as in the difficult discrimination group, but not in the 50% contingency control. The difficult discrimination group did not exhibit differential UCS expectancy but did show clear differential SCR. These observations support a dual process interpretation of classical conditioning whereby conditioning on an implicit level can occur without explicit knowledge about the contingencies.  相似文献   
992.
Tic disorders are heterogeneous, with symptoms varying widely both within and across patients. Exploration of symptom clusters may aid in the identification of symptom dimensions of empirical and treatment import. This article presents the results of two studies investigating tic symptom clusters using a sample of 99 youth (M age = 10.7, 81% male, 77% Caucasian) diagnosed with a primary tic disorder (Tourette’s disorder or chronic tic disorder), across two university-based outpatient clinics specializing in tic and related disorders. In Study 1, a cluster analysis of the Yale Global Tic Severity Scale (YGTSS) identified four symptom dimensions: predominantly complex tics; simple head/face tics; simple body tics; and simple vocal/facial tics. In Study 2, these clusters were shown to be differentially associated with demographic and clinical characteristics. Findings lend support to prior research on tic phenomenology, help to organize treatment goals, and suggest symptom dimensions of tic disorders for further evaluation.  相似文献   
993.
994.
The variable-criteria sequential stopping rule (SSR) is a method for conducting planned experiments in stages after the addition of new subjects until the experiment is stopped because the p value is less than or equal to a lower criterion and the null hypothesis has been rejected, the p value is above an upper criterion, or a maximum sample size has been reached. Alpha is controlled at the expected level. The table of stopping criteria has been validated for a t test or ANOVA with four groups. New simulations in this article demonstrate that the SSR can be used with unequal sample sizes or heterogeneous variances in a t test. As with the usual t test, the use of a separate-variance term instead of a pooled-variance term prevents an inflation of alpha with heterogeneous variances. Simulations validate the original table of criteria for up to 20 groups without a drift of alpha. When used with a multigroup ANOVA, a planned contrast can be substituted for the global F as the focus for the stopping rule. The SSR is recommended when significance tests are appropriate and when the null hypothesis can be tested in stages. Because of its efficiency, the SSR should be used instead of the usual approach to the t test or ANOVA when subjects are expensive, rare, or limited by ethical considerations such as pain or distress.  相似文献   
995.
In this paper, several examples from the literature, and one central new one, are used as case studies of texts of discourse containing an argumentation scheme that has now been widely investigated in literature on argumentation. Argumentation schemes represent common patterns of reasoning used in everyday conversational discourse. The most typical ones represent defeasible arguments based on nonmonotonic reasoning. Each scheme has a matching set of critical questions used to evaluate a particular argument fitting that scheme. The project is to study how to build a formal computational model of this scheme for the circumstantial ad hominem argument using argumentation tools and systems developed in artificial intelligence. It is shown how the formalization built using these tools is applicable to the tasks of identification, analysis and evaluation of the central case studied. One important implication of the work is that it provides a foundational basis for showing how other argumentation schemes can be formalized.  相似文献   
996.
Panel data collected in 1991 as part of the University of Southern California Longitudinal Study of Generations (LSOG) were used to predict reported preparation activities prior to and in response to the 1994 Northridge, California, earthquake. In late 1994 and early 1995, 163 panelists (representing 107 multigenerational families) were interviewed by phone about their earthquake experiences. The best 1991 predictor of pre‐quake preparation was the extent of instrumental support respondents provided to network members. Earthquake preparation activities undertaken after the quake were associated with the amount and cost of damage experienced during the quake, 1991 neuroticism scores, age (inversely), and having preparedness encouraged by multiple network sources. The results highlight the importance of social roles (e.g., support provision) and discussion by informal network sources in the adoption of public health and safety messages.  相似文献   
997.
998.
Situations can be seen as having attributes or qualities in much the same way as people have traits. The structure of people's perceptions of these situation qualities was explored. A comprehensive list of adjectives that might describe situations was generated, and people rated situations using samples of the words. Across several samples of words and participants and several analytic methods, four factors show up regularly (positivity, negativity, productivity, and ease of negotiation). In a second study, it was shown that these factors predict the way in which people freely sort situations. The conceptual nature of these factors and of situation qualities is discussed, with particular emphasis on how people's goals and perceived outcomes influence their perceptions of situations. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   
999.
In this study, we investigated the moderating role of interdependence (a personality trait that measures the extent to which individuals desire working in a group‐based, cooperative setting) on the relationship between competitiveness and one‐year objective sales performance. On the basis of data from 133 sales representatives, results indicated that: (a) competitiveness was related to objective sales performance; and (b) interdependence moderated the relationship between competitiveness and objective sales performance such that competitiveness predicted objective sales performance more strongly for those who scored low in interdependence versus those who scored high in interdependence. Implications for sales selection and reward systems and directions for future research are considered.  相似文献   
1000.
Douglas Walton 《Synthese》2006,152(2):237-284
This paper addresses the problem posed by the current split between the two opposed hypotheses in the growing literature on the fallacy of begging the question the epistemic hypothesis, based on knowledge and belief, and the dialectical one, based on formal dialogue systems. In the first section, the nature of split is explained, and it is shown how each hypothesis has developed. To get the beginning reader up to speed in the literature, a number of key problematic examples are analyzed illustrating how both approaches can be applied. Useful tools are brought to bear on them, including the automated argument diagramming system Araucaria, and profiles of dialogue used to represent circular argumentation in a dialogue tableau format. These tools are used to both to model circular reasoning and to provide the contextual evidence needed to properly determine whether the circular reasoning in a given case is better judged fallacious or not. A number of technical problems that have impeded the development of both hypotheses are studied. One central problem is the distinction between argument and explanation. It is concluded that the best way to move forward and solve these problems is to reformulate the two hypotheses in such a way that they might be able to co-exist. On this basis, a unified methodology is proposed that allows each hypothesis to move forward as a legitimate avenue for research using the same tools.  相似文献   
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