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991.
A general class of labeled sequent calculi is investigated, and necessary and sufficient conditions are given for when such a calculus is sound and complete for a finite-valued logic if the labels are interpreted as sets of truth values (sets-as-signs). Furthermore, it is shown that any finite-valued logic can be given an axiomatization by such a labeled calculus using arbitrary "systems of signs," i.e., of sets of truth values, as labels. The number of labels needed is logarithmic in the number of truth values, and it is shown that this bound is tight. 相似文献
992.
This paper investigates the role of conditionals in hypothetical reasoning and rational decision making. Its main result is
a proof of a representation theorem for preferences defined on sets of sentences (and, in particular, conditional sentences),
where an agent’s preference for one sentence over another is understood to be a preference for receiving the news conveyed
by the former. The theorem shows that a rational preference ordering of conditional sentences determines probability and desirability
representations of the agent’s degrees of belief and desire that satisfy, in the case of non-conditional sentences, the axioms
of Jeffrey’s decision theory and, in the case of conditional sentences, Adams’ expression for the probabilities of conditionals.
Furthermore, the probability representation is shown to be unique and the desirability representation unique up to positive
linear transformation.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
993.
994.
995.
Taking seriously the implications of post-colonial theory, the authors revisit the introductory course (normally “World Religions”) as a course on the plurality of religions in contemporary U.S. culture. They explain the structure of the course, and discuss practical and ethical issues around student field visits to learn about other religions. 相似文献
996.
Richard A. Chechile 《Behavior research methods》1998,30(2):227-231
A classic data-analytic problem is the statistical evaluation of the distributional form of interval-scale scores. The investigator may need to know whether the scores originate from a single Gaussian distribution or from a mixture of Gaussian distributions or from a different probability distribution. The relative merits of extant goodness-of-fit metrics are discussed. Monte Carlo power analyses are provided for several of the more powerful goodness-of-fit metrics. 相似文献
997.
Richard A. Abrams Heather M. Oonk Jay Pratt 《Attention, perception & psychophysics》1998,60(2):201-208
Subjects produced saccades to continuously visible targets that were signaled by the pitch, not the location, of an auditory signal. Such endogenous saccades were initiated more quickly when the visual fixation point disappeared 200 msec before the signal (thus producing a “gap”), even though the alerting benefits of such a warning were eliminated by an earlier warning tone. The presence of the gap effect under these circumstances shows that the effect is more general than was previously believed: Visual fixation point offsets facilitate saccades by affecting oculomotor processes related to both visually elicited (exogenous) and centrally produced (endogenous) saccades. In addition, the magnitude of the gap effect for endogenous saccades was significantly smaller than that for exogenous saccades, suggesting that at least some of the effect arises in relatively early processes, such as those involved in the processing of sensory signals, and not exclusively in later processes, such as those involved in the preparation and production of saccades. 相似文献
998.
Daniel D. Mccall Richard L. Freyman Rachel K. Clifton 《Attention, perception & psychophysics》1998,60(4):593-601
The effect of changing the frequency components of an echo relative to the sound source was examined in a two-choice discrimination task. Subjects sat in an anechoic chamber and discriminated the direction of the lag noise burst within a lead-lag pair presented over loudspeakers. The leading noise burst was broadband, and the lagging burst was either high- or low-pass filtered. On some conditions, this test burst pair was preceded by a conditioning train of burst pairs, which also had a broadband lead and either a high- or low-frequency lag. When the frequency content of the echo was held constant across the conditioning train and test burst pair, echo suppression that was built up during the repeating train was maintained for the test burst pair, shown by the subjects’ poor performance in detecting the location of the lagging burst. By comparison, subjects had little difficulty in localizing the lagging burst when the frequency content of the echo changed between the conditioning train and the test burst, indicating that any buildup of suppression during the train was broken when the lagging burst’s spectrum shifted. The data are consistent with an interpretation in which echo suppression is temporarily broken when listeners’ built-up expectations about room acoustics are violated. 相似文献
999.
The subject of factor indeterminacy has a vast history in factor analysis (Guttman, 1955; Lederman, 1938; Wilson, 1928). It has lead to strong differences in opinion (Steiger, 1979). The current paper gives necessary and sufficient conditions for observability of factors in terms of the parameter matrices and a finite number of variables. Five conditions are given which rigorously define indeterminacy. It is shown that (un)observable factors are (in)determinate. Specifically, the indeterminacy proof by Guttman is extended to Heywood cases. The results are illustrated by two examples and implications for indeterminacy are discussed. 相似文献
1000.
Richard King 《亚洲哲学》1998,8(1):5-17
Contemporary accounts of early Mahāyāna Buddhist schools like the Madhyamaka and the Yogācāra tend to portray them as generally antithetical to the Abhidharma of non‐Mahāyāna schools such as the Theravāda and the Sarvāstivāda. This paper attempts to locate early Yogācāra philosophical speculation firmly within the broader context of Abhidharma debates. Certain key Yogācāra concepts such as ālayavijñāna, vijñapti‐mātratā and citta‐mātra are discussed insofar as they relate to pre‐existing concepts and issues found in the Vaibhāsika and Sautrāntika schools, with specific reference to the Abhidharmako?a and the corresponding bhāsya of Vasubandhu. Finally, some remarks are made about the, benefits of approaching the history of religious ideas without the benefits and distortions of hindsight, particularly as this relates to the attribution of an idealistic position to the early Yogācāra literature. 相似文献