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181.
Till Grüne-Yanoff 《Synthese》2009,169(3):539-555
It is often claimed that artificial society simulations contribute to the explanation of social phenomena. At the hand of a particular example, this paper argues that artificial societies often cannot provide full explanations, because their models are not or cannot be validated. Despite that, many feel that such simulations somehow contribute to our understanding. This paper tries to clarify this intuition by investigating whether artificial societies provide potential explanations. It is shown that these potential explanations, if they contribute to our understanding, considerably differ from potential causal explanations. Instead of possible causal histories, simulations offer possible functional analyses of the explanandum. The paper discusses how these two kinds explanatory strategies differ, and how potential functional explanations can be appraised.  相似文献   
182.
In this article, I attempt to merge two themes. First, there is often a large gap between high hopes about impacts of policies or programs and the demonstrated results. I describe four keys/threats to success in any social problem area: theory, implementation, evaluation, and resource/system support. Second, I present theory and research from over 30 years of work on participation, conducted by my colleagues and myself that can illuminate and be illuminated by theory, implementation, evaluation, and resource/system support. I offer ideas for solutions that increase the probability of success. I conclude with the need to have high hopes tempered by theory and research to develop realistically ambitious solutions to social problems.  相似文献   
183.
The study explored the effect of the subjective evaluation and of BIS/BAS (Behavioral Inhibition and Activation System) differences on psychophysiological and brain oscillation measures, in response to pleasant/unpleasant and high/low arousing stimuli. Skin conductance response, heart rate, and electromyography, and alpha frequency band, were registered, during viewing IAPS figures. Both BIS and BAS measures were significant in modulating behavioral, autonomic and brain responses, with a clear dichotomy BAS-appetitive/positive BIS-withdrawal/negative sensitivity. Withdrawal (BIS) and appetitive (BAS) behavior showed opposite patterns of responses by the subjects within the frontal cortical site more than other sites. In addition, a specific frontal lateralization effect was found as a function of BIS (more right-side activation for negative cues) and BAS (more left-side activation for positive cues). Moreover, autonomic variables and frequency band were found to be effected by arousal rating per se, with an increased response to high arousal in comparison with low arousal and neutral stimuli. The effects of subjective evaluation and individual differences were discussed in the light of the coping activity of emotion comprehension.  相似文献   
184.
We analyzed family dynamics and coping behaviors of parents with a child with an autistic spectrum disorder. Previous research suggests that moderate levels of cohesion and adaptability are associated with higher levels of positive coping, and that the more coping strategies a family implements, the greater their satisfaction with family functioning. Using a family systems approach, the relationships among the familial variables of cohesion, adaptability, and social support were evaluated for their contributions to coping in the family unit. We also compared the responses of mothers and fathers. Surprisingly, for these parents of children with autism, those who rated their family as enmeshed implemented more positive coping strategies than did those from other cohesion styles. This finding suggests that the enmeshed style may be more adaptive for a family that encounters extreme challenges. Notably, mothers and fathers agreed on all variables except for perception of social support from family and friends. Mothers perceived more social support from family and friends. The results lead to several interesting suggestions for future research.  相似文献   
185.
Two classes of π are studied whose properties are similar to those of the protoalgebraic deductive systems of Blok and Pigozzi. The first is the class of N-protoalgebraic π-institutions and the second is the wider class of N-prealgebraic π-institutions. Several characterizations are provided. For instance, N-prealgebraic π-institutions are exactly those π-institutions that satisfy monotonicity of the N-Leibniz operator on theory systems and N-protoalgebraic π-institutions those that satisfy monotonicity of the N-Leibniz operator on theory families. Analogs of the correspondence property of Blok and Pigozzi for π-institutions are also introduced and their connections with preand protoalgebraicity are explored. Finally, relations of these two classes with the (, N)-algebraic systems, introduced previously by the author as an analog of the -algebras of Font and Jansana, and with an analog of the Suszko operator of Czelakowski for π-institutions are also investigated. Presented by Josep Maria Font  相似文献   
186.
In this paper, we show that Arrow’s well-known impossibility theorem is instrumental in bringing the ongoing discussion about verisimilitude to a more general level of abstraction. After some preparatory technical steps, we show that Arrow’s requirements for voting procedures in social choice are also natural desiderata for a general verisimilitude definition that places content and likeness considerations on the same footing. Our main result states that no qualitative unifying procedure of a functional form can simultaneously satisfy the requirements of Unanimity, Independence of irrelevant alternatives and Non-dictatorship at the level of sentence variables. By giving a formal account of the incompatibility of the considerations of content and likeness, our impossibility result makes it possible to systematize the discussion about verisimilitude, and to understand it in more general terms.  相似文献   
187.
We give complete sequent-like tableau systems for the modal logics KB, KDB, K5, and KD5. Analytic cut rules are used to obtain the completeness. Our systems have the analytic superformula property and can thus give a decision procedure. Using the systems, we prove the Craig interpolation lemma for the mentioned logics.  相似文献   
188.
This article examines strategic framing efforts within the president's inner circle of foreign policy advisors. The comparative case study method is used to describe and explain the framing process involved in President Jimmy Carter's arms control decisions with respect to the Soviet Union. Carter's two central foreign policy advisors, National Security Advisor Zbigniew Brzezinski and Secretary of State Cyrus Vance, portrayed the Soviets in very different terms. The premise underlying this study is that advisors attempt to frame their policy preferences favorably in order to influence the group process and the president's policy choice. Advisors do so by playing up the positive aspects of an option and downplaying any negative aspects. Three components of the framing process are explored: historical/cultural symbolism, personal beliefs and values, and political cost assessments.  相似文献   
189.
190.
To search for genetic influence on human fertility differentials appears inconsistent with past empirical research and prior interpretations of Fisher's fundamental theorem of natural selection. We discuss Fisher's theorem and give reasons why genetic influences may indeed account for individual differences in human fertility. We review recent empirical studies showing genetic influence on variance in fertility outcomes and precursors to fertility. Further, some of the genetic variance underlying fertility outcomes overlaps with that underlying fertility precursors. Findings from different cultures, different times, different levels of data, and both behavioral and molecular genetic designs lead to the same conclusion: Fertility differentials are genetically influenced, and at least part of the influence derives from behavioral precursors that are under volitional control, which are themselves genetically mediated.  相似文献   
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