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971.
Beyond Positivist Ecology: Toward an Integrated Ecological Ethics   总被引:2,自引:2,他引:0  
A post-positivist understanding of ecological science and the call for an “ecological ethic” indicate the need for a radically new approach to evaluating environmental change. The positivist view of science cannot capture the essence of environmental sciences because the recent work of “reflexive” ecological modelers shows that this requires a reconceptualization of the way in which values and ecological models interact in scientific process. Reflexive modelers are ecological modelers who believe it is appropriate for ecologists to examine the motives for their choices in developing models; this self-reflexive approach opens the door to a new way of integrating values into public discourse and to a more comprehensive approach to evaluating ecological change. This reflexive building of ecological models is introduced through the transformative simile of Aldo Leopold, which shows that learning to “think like a mountain” involves a shift in both ecological modeling and in values and responsibility. An adequate, interdisciplinary approach to ecological valuation, requires a re-framing of the evaluation questions in entirely new ways, i.e., a review of the current status of interdisciplinary value theory with respect to ecological values reveals that neither of the widely accepted theories of environmental value—neither economic utilitarianism nor intrinsic value theory (environmental ethics)—provides a foundation for an ecologically sensitive evaluation process. Thus, a new, ecologically sensitive, and more comprehensive approach to evaluating ecological change would include an examination of the metaphors that motivate the models used to describe environmental change.
Bryan G. NortonEmail:
  相似文献   
972.
In connectionism and its offshoots, models acquire functionality through externally controlled learning schedules. This undermines the claim of these models to autonomy. Providing these models with intrinsic biases is not a solution, as it makes their function dependent on design assumptions. Between these two alternatives, there is room for approaches based on spontaneous self-organization. Structural reorganization in adaptation to spontaneous activity is a well-known phenomenon in neural development. It is proposed here as a way to prepare connectionist models for learning and enhance the autonomy of these models.  相似文献   
973.
3~4岁儿童规则因果推理能力的训练研究   总被引:1,自引:0,他引:1       下载免费PDF全文
学前期是儿童多种推理能力产生和发展的重要时期。本研究(以64名3岁儿童为被试,采用Frye和Zelazo等所设计的“二进二出”装置,通过对3岁儿童的规则因果推理能力进行训练,从而探索儿童规则因果推理的内在机制。在本研究条件下,结果发现:1.年龄与训练的交互效应不显著,各年龄组儿童经过训练后,成绩的提高没有显著差异;2.规则与训练的交互效应显著,竖直规则下,儿童通过训练后提高的成绩不显著,但在交叉规则下前测后测成绩差异极其显著;3.训练效应显著,暴露因果机制,给予及时反馈和阐述规则时附加手势这些信息能促进年幼儿童对高级规则的掌握。  相似文献   
974.
For a study with multinomial data where there are ng individuals and with each person having nr test trials, the question arises as to how to fit the parameters of a multinomial processing tree (MPT) model. Should each parameter be estimated for each individual and then averaged to obtain a group estimate, or should the frequencies in the multinomial categories be pooled so that the model is fit once for the entire group? This basic question is explored with a series of Monte Carlo simulations for some prototypical MPT models. There is a general finding of a pooling advantage for the case where there is a single experimental condition. Also when there are different experimental conditions, there is reduced bias for detecting condition differences for a method based on the pooled data. Although the focus of the paper is on multinomial models, a general theorem is advanced that establishes a basic condition that determines whether there is or is not a difference between the averaging of individual estimates and the estimate based on the pooled data.  相似文献   
975.
This paper provides a new formalization for the class of binary multinomial processing tree (BMPT) models, and theorems for the class are developed using the formalism. MPT models are a popular class of information processing models for categorical data in specific cognitive paradigms. They have a recursive structure that is productively described with the tools of formal language and computation theory. We provide an axiomatization that characterizes BMPT models as strings in a context-free language, and then we add model-theoretic axioms and definitions to interpret the strings as parameterized probabilistic models for categorical data. The language for BMPT models is related to the Full Binary Tree language, a well-studied context-free language. Once BMPT models are viewed from the perspective of the Full Binary Tree language, a number of theoretical and computational results can be developed. In particular, we have a number of results concerning the enumerations of BMPT models as well as the identifiability of subclasses of these models.  相似文献   
976.
In an ethnically diverse sample of 195 married couples, we conducted a latent factor growth analysis to investigate the longitudinal link (4 time points over 4½ years) between marital aggression (physical and verbal aggression self‐ and partner‐reports) and individual internalizing symptoms (depression and anxiety) as they relate to trajectories of alcohol use among husbands and wives. Alcohol use was operationalized as a latent factor with self‐ and partner reports of problem drinking as measured by the Michigan Alcoholism Screening Test and the Alcohol Dependence Scale. Verbal aggression by husbands or wives, by itself, has no effect on their alcohol use over time. In conjunction with depression, however, verbally aggressive husbands do have elevated drinking levels. The effects of husbands' and wives' physical aggression on their own and their partners' drinking behavior were also significant. This study is one of the first to examine the change over time in alcohol use for marital partners as related to marital aggression and internalizing symptoms. Our results shed light on areas of marital functioning (aggression, internalizing, alcohol use) that have not been investigated in conjunction with each other in a longitudinal design. Aggr. Behav. 35:296–312, 2009. © 2009 Wiley‐Liss, Inc.  相似文献   
977.
This research examines the relationship between childhood physical and sexual abuse and the types of crimes committed by male adult offenders. We use the method of discriminant prediction to determine whether independent and dependent variables are related in ways that theories predict. Our analyses of data from the Survey of Inmates in State and Federal Correctional Facilities suggest that offenders model specific behaviors to which they have been exposed. Male offenders who were sexually abused as a child are more likely to commit sexual offenses, particularly sexual offenses against children, than nonsexual offenses. Offenders who were physically abused are more likely to engage in violent offenses than nonviolent offenses. Further analyses show that sexual offenders, and to a lesser extent violent offenders, are likely to specialize in those offenses. Our results are consistent with a social learning approach. They address a heretofore neglected issue: what exactly do children model when they are mistreated. Aggr. Behav. 35:489–501, 2009. © 2009 Wiley‐Liss, Inc.  相似文献   
978.
It has recently been suggested that the concept of Functional Impulsivity bears some similarity to the sensitivity of the Behavioral Activation System (BAS; Smillie & Jackson, 2006). In the present research we take a closer look at this idea, testing more specific hypotheses on the associations of different BAS-related components with Functional and Dysfunctional Impulsivity. Analyzing a sample of 719, we found that the Drive component was uniquely connected with Functional Impulsivity, and Fun Seeking was linked to both impulsivities, but more weakly so to Functional Impulsivity compared with Drive. Reward Responsiveness was unrelated to Impulsivity. Implications for the conceptualization of Functional Impulsivity and for a complex view of BAS-related functions are addressed.  相似文献   
979.
This paper offers a conceptual framework which (re)integrates goal-directed control, motivational processes, and executive functions, and suggests a developmental pathway from situated action to higher level cognition. We first illustrate a basic computational (control-theoretic) model of goal-directed action that makes use of internal modeling. We then show that by adding the problem of selection among multiple action alternatives motivation enters the scene, and that the basic mechanisms of executive functions such as inhibition, the monitoring of progresses, and working memory, are required for this system to work. Further, we elaborate on the idea that the off-line re-enactment of anticipatory mechanisms used for action control gives rise to (embodied) mental simulations, and propose that thinking consists essentially in controlling mental simulations rather than directly controlling behavior and perceptions. We conclude by sketching an evolutionary perspective of this process, proposing that anticipation leveraged cognition, and by highlighting specific predictions of our model.
Cristiano CastelfranchiEmail:
  相似文献   
980.
Evidence from numerous studies using the visual world paradigm has revealed both that spoken language can rapidly guide attention in a related visual scene and that scene information can immediately influence comprehension processes. These findings motivated the coordinated interplay account ( Knoeferle & Crocker, 2006 ) of situated comprehension, which claims that utterance-mediated attention crucially underlies this closely coordinated interaction of language and scene processing. We present a recurrent sigma-pi neural network that models the rapid use of scene information, exploiting an utterance-mediated attentional mechanism that directly instantiates the CIA. The model is shown to achieve high levels of performance (both with and without scene contexts), while also exhibiting hallmark behaviors of situated comprehension, such as incremental processing, anticipation of appropriate role fillers, as well as the immediate use, and priority, of depicted event information through the coordinated use of utterance-mediated attention to the scene.  相似文献   
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