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31.
In this review, we consider three possible criteria by which knowledge might be regarded as implicit or inaccessible: It might be implicit only in the sense that it is difficult to articulate freely, or it might be implicit according to either an objective threshold or a subjective threshold. We evaluate evidence for these criteria in relation to artificial grammar learning, the control of complex systems, and sequence learning, respectively. We argue that the convincing evidence is not yet in, but construing the implicit nature of implicit learning in terms of a subjective threshold is most likely to prove fruitful for future research. Furthermore, the subjective threshold criterion may demarcate qualitatively different types of knowledge. We argue that (1) implicit, rather than explicit, knowledge is often relatively inflexible in transfer to different domains, (2) implicit, rather than explicit, learning occurs when attention is focused on specific items and not underlying rules, and (3) implicit learning and the resulting knowledge are often relatively robust.  相似文献   
32.
The present paper introduces theP system as a scheme for organizing Pavlovian procedures in an orderly and comprehensive manner. The system is defined by three temporal variables and three restrictions on their possible values. It can be used to define all standard temporal variables—namely, stimulus duration, interstimulus interval, trace interval, and intertrial interval—as well as variables C and T of scalar expectancy theory. The system also permits the definition of new independent variables through combinations of the basic temporal parameters. We exemplify this possibility by defining two ratios of temporal intervals. These ratios lead to a space where traditional Pavlovian arrangements (viz., simultaneous, forward-trace, forward-delay, backward) become points on a continuum, and optimal conditions across different experimental preparations become equivalent. Finally, the system can be used to define contingency variables such asp(US/CS),p(US/~CS), and the phi coefficient (φ). In this manner, an organization of different kinds of Pavlovian procedures is achieved on the basis of a single parametric scheme. Such an organization facilitates establishing procedural and theoretical relationships between temporal and contingency variables. The paper concludes with a discussion of certain limitations of the system and other related issues  相似文献   
33.
Hájek  Petr 《Studia Logica》1997,58(1):129-141
A very simple many-valued predicate calculus is presented; a completeness theorem is proved and the arithmetical complexity of some notions concerning provability is determined.  相似文献   
34.
Among the factors impeding the development of the discipline of psychology in Latin America, emphasis must be given to the lack of infrastructural conditions. Also important is the lack of social, economic, and political stability, leading to inadequate administrative and financial support for research. The high degree of uncertainty as to the future of societal outcomes leads to short-term planning, and weakens the possibility of sustained lines of research. Yet, the same economic and political crises have positive consequences: A growing awareness of social problems and a realization of the utility of psychology in their solutions. The resultant job opportunities for graduates, and a generation of “engaged” professionals, are all helping the growth of an indigenous psychology. Increasing participation of Latin American psychologists in international congresses, particularly those of the Interamerican Society of Psychology, has had laudatory effects on the development of the discipline in the region.  相似文献   
35.
Genetic counseling for women of advanced maternal age who are considering prenatal testing continues to be based on a principle of nondirectiveness. We interviewed 11 genetic counseling students and four counselors about how they experience and manage, in practice, the tensions between the ideology of nondirectiveness and the acknowledged reality that one can never be truly nondirective. We found that our respondents creatively resolve this tension—simultaneously resisting and adhering to the values of nondirectiveness and information-giving—in individual and situation-specific ways. This resolution is facilitated by the extent to which information given to counselees is fluid, mobile and context-dependent, but these very features of information also have critical implications for both the norms and the practice of genetic counseling.  相似文献   
36.
Summary Two experiments investigated relative spatial coding in the Simon effect. It was hypothesized that relative spatial coding is carried out with reference to the position of the focus of visual attention. The spatial code for an imperative stimulus presented exactly at the position of focal attention should be neutral on the horizontal plane, and therefore no Simon effect should be observed. However, when the imperative stimulus is presented to the left or to the right of the current position of focal attention, the spatial code should not be neutral, thus producing a Simon effect. In both experiments, focal attention was manipulated either by a peripherally presented onset precue (Experiment 1) or by a centrally presented symbolic precue (Experiment 2). Results showed that the Simon effect was substantially reduced in both experiments when a valid precue preceded the imperative stimulus just in time to conclude refocusing of attention to the position of the imperative stimulus before it was presented. However, conditions with neutral precues yielded a normally sized Simon effect. In both experiments, the Simon effect decreased as the SOA grew when the precue was valid. At least for the Simon effect, the results can be interpreted as evidence that relative spatial coding is functionally related to the position of the focus of attention.  相似文献   
37.
38.
Zellini (1979, Theorem 3.1) has shown how to decompose an arbitrary symmetric matrix of ordern ×n as a linear combination of 1/2n(n+1) fixed rank one matrices, thus constructing an explicit tensor basis for the set of symmetricn ×n matrices. Zellini's decomposition is based on properties of persymmetric matrices. In the present paper, a simplified tensor basis is given, by showing that a symmetric matrix can also be decomposed in terms of 1/2n(n+1) fixed binary matrices of rank one. The decomposition implies that ann ×n ×p array consisting ofp symmetricn ×n slabs has maximal rank 1/2n(n+1). Likewise, an unconstrained INDSCAL (symmetric CANDECOMP/PARAFAC) decomposition of such an array will yield a perfect fit in 1/2n(n+1) dimensions. When the fitting only pertains to the off-diagonal elements of the symmetric matrices, as is the case in a version of PARAFAC where communalities are involved, the maximal number of dimensions can be further reduced to 1/2n(n–1). However, when the saliences in INDSCAL are constrained to be nonnegative, the tensor basis result does not apply. In fact, it is shown that in this case the number of dimensions needed can be as large asp, the number of matrices analyzed.  相似文献   
39.
Increasingly, contemporary medical ethicists have become aware of the need to explicate a foundation for their various models of applied ethics. Many of these theories are inspired by the apparent incompatibility of patient autonomy and provider beneficence. The principle of patient autonomy derives its current primacy to a large extent from its legal origins. However, this principle seems at odds with the clinical reality. In the bioethical literature, the notion of authenticity has been proposed as an alternative foundational principle to autonomy. This article examines this proposal in reference to various existentialist philosophers (Heidegger, Sartre, Camus and Marcel). It is concluded that the principle of autonomy fails to do what it is commonly supposed to do: provide a criterion of distinction that can be invoked to settle moral controversies between patients and providers. The existentialist concept of authenticity is more promising in at least one crucial respect: It acknowledges that the essence of human life disappears from sight if life's temporal character is reduced to a series of present decisions and actions. This also implies that the very quest for a criterion that allows physicians to distinguish between sudden, unexpected decisions of their patients to be or not to be respected, without recourse to the patient's past or future, is erroneous.  相似文献   
40.
The purpose of this paper is to evaluate the significance of the existential notion of authenticity for medical ethics. This is done by analyzing authenticity and examining its implications for the patient-professional relationship and for ethical decision-making in medical situations. It is argued that while authenticity implies important demand for individual responsibility, which has therapeutic significance, it perpetuates ideas which are antithetical both to authentic interaction between patients and professionals and to fruitful deliberation of moral dilemmas. In order to counteract these consequences, an alternative idea of authenticity is introduced. According to this idea, authenticity is not regarded primarily as individual sovereignty, but as an ability to participate in a dialogue in which the subjectivity of both partners is respected. Such practice, based on mutual trust and responsibility, would enhance common decision-making and overcome the alienation between patients and professionals.  相似文献   
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