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1.
D. Scott in his paper [5] on the mathematical models for the Church-Curry -calculus proved the following theorem.A topological space X. is an absolute extensor for the category of all topological spaces iff a contraction of X. is a topological space of Scott's open sets in a continuous lattice.In this paper we prove a generalization of this theorem for the category of , -closure spaces. The main theorem says that, for some cardinal numbers , , absolute extensors for the category of , -closure spaces are exactly , -closure spaces of , -filters in , >-semidistributive lattices (Theorem 3.5).If = and = we obtain Scott's Theorem (Corollary 2.1). If = 0 and = we obtain a characterization of closure spaces of filters in a complete Heyting lattice (Corollary 3.4). If = 0 and = we obtain a characterization of closure space of all principial filters in a completely distributive complete lattice (Corollary 3.3).  相似文献   

2.
Universality of generalized Alexandroff's cube plays essential role in theory of absolute retracts for the category of , -closure spaces. Alexandroff's cube. is an , -closure space generated by the family of all complete filters. in a lattice of all subsets of a set of power .Condition P(, , ) says that is a closure space of all , -filters in the lattice ( ), .Assuming that P (, , ) holds, in the paper [2], there are given sufficient conditions saying when an , -closure space is an absolute retract for the category of , -closure spaces (see Theorems 2.1 and 3.4 in [2]).It seems that, under assumption that P (, , ) holds, it will be possible to givean uniform characterization of absolute retracts for the category of , -closure-spaces.Except Lemma 3.1 from [1], there is no information when the condition P (, , ) holds or when it does not hold.The main result of this paper says, that there are examples of cardinal numbers, , , such that P (, , ) is not satisfied.Namely it is proved, using elementary properties of Lebesgue measure on the real line, that the condition P (, 1, 2 ) is not satisfied.Moreover it is shown that fulfillment of the condition is essential assumption in, Theorems 2.1 and 3.4 from [1] i.e. it cannot be eliminated.  相似文献   

3.
Summary In this study on Wilde's phenomenon (Wilde 1950) the two components of disparity, one of them processing displacement, and the other one apparent rotation, are analysed in terms of dependence on the disparity of the end-lines of the pattern (), and on the percentage of magnification (M) of one of the monocular patterns in relation to the other one. It was found that the component of disparity for displacement ' can be expressed as a linear regression equation '=–a+b.The component of disparity for rotation, expressed as a percentage of magnification effective for rotation (M) can be expressed as M=a–b1+b2M.It was concluded that the two components of disparity are processed through independent parallel channels, the processing of the component of disparity for displacement being the faster process, accounting for the larger part of the total disparity.  相似文献   

4.
5.
This article aims at elucidating the logic of Arist. SE 22, 178b36–179a10 and, in particular, of the sophism labelled "Third Man" discussed in it. I suggest that neither the sophistic Walking Man argument, proposed by ancient commentators, nor the Aristotelian Third Man of the , suggested by modern interpreters, can be identified with the fallacious argument Aristotle presents and solves in the passage. I propose an alternative reconstruction of the Third Man sophism and argue that an explanation of the lines regarding the identity of Coriscus and Coriscus the musician (178b39–179a3) is indispensable for its correct understanding, since they hint at another sophism in some important aspects analogous. Finally, I show that two contradictions concerning spotted by scholars in the passage are only apparent and can be dissolved once the assumption that the anti-Platonic Third Man argument is at stake here is discarded, and once the passage is read in the light of its agonistic context.  相似文献   

6.
We derive several relationships between communalities and the eigenvalues for ap ×p correlation matrix under the usual factor analysis model. For suitable choices ofj, j (), where j () is thej-th largest eigenvalue of , provides either a lower or an upper bound to the communalities for some of the variables. We show that for at least one variable, 1 - p () improves on the use of squared mulitiple correlation coefficient as a lower bound.This research was done while the second author was at Tokyo Institute of Technology.  相似文献   

7.
Basic Predicate Logic, BQC, is a proper subsystem of Intuitionistic Predicate Logic, IQC. For every formula in the language {, , , , , , }, we associate two sequences of formulas 0,1,... and 0,1,... in the same language. We prove that for every sequent , there are natural numbers m, n, such that IQC , iff BQC n m. Some applications of this translation are mentioned.  相似文献   

8.
The author has previously introduced an operator into dynamic logic which takes formulae to terms; the suggested reading of A was the bringing about of A or the seeing to it that A. After criticism from S. K. Thomason and T. J. Surendonk the author now presents an improved version of his theory. The crucial feature is the introduction of an operatorOK taking terms to formulae; the suggested reading of OK is always terminates.  相似文献   

9.
Tre: Wstp. I. Definicje arbitralne. II. Syntetyczne konsekwencje definicji arbitralnych III. Analityczne i rzeczowe komponenty definicji arbitralnych. IV. Zdania analityczne.Artyku ten w nieznacznym tylko stopniu róni si od pracy doktorskiej, któr przedstawiem w 1962 r. Jak najuprzejmiej dzikuj Prof. Dr M. Kokoszyskiej-Lutman, Prof. Dr J. Supeckiemu oraz Doc. Dr M. Przeckiemu za szereg uwag i wskazówek, z których tak wiele skorzystaem przygotowujc ostateczn redakcj pracy.  相似文献   

10.
11.
The partial credit model is considered under the assumption of a certain linear decomposition of the item × category parameters ih into basic parameters j. This model is referred to as the linear partial credit model. A conditional maximum likelihood algorithm for estimation of the j is presented, based on (a) recurrences for the combinatorial functions involved, and (b) using a quasi-Newton approach, the so-called Broyden-Fletcher-Goldfarb-Shanno (BFGS) method; (a) guarantees numerically stable results, (b) avoids the direct computation of the Hesse matrix, yet produces a sequence of certain positive definite matricesB k ,k=1, 2, ..., converging to the asymptotic variance-covariance matrix of the . The practicality of these numerical methods is demonstrated both by means of simulations and of an empirical application to the measurement of treatment effects in patients with psychosomatic disorders.The authors thank one anonymous reviewer for his constructive comments. Moreover, they thankfully acknowledge financial support by the Österreichische Nationalbank (Austrian National Bank) under Grant No. 3720.  相似文献   

12.
Most philosophers believe that the Liar Paradox is semantical in character, and arises from difficulties in the predicate true. The author argues that the paradox is pragmatic, not semantic, and arises from violations of essential conditions that define statement-making speech acts. The author shows that his solution to the paradox will not only handle the classical Liar sentences that are necessarily or intrinsically paradoxical, but also sets of Kripke-sentences that are contingently paradoxical.  相似文献   

13.
Important positive as well as negative results on interpolation property in fragments of the intuitionistic propositional logic (INT) were obtained by J. I. Zucker in [6]. He proved that the interpolation theorem holds in purely implicational fragment of INT. He also gave an example of a fragment of INT for which interpolation fails. This fragment is determined by the constant falsum (), well known connectives: implication () and conjunction (), and by a ternary connective defined as follows: (p, q, r)= df (pq)(pr).Extending this result of J. I. Zucker, G. R. Renardel de Lavalette proved in [5] that there are continuously many fragments of INT without the interpolation property.This paper is meant to continue the research mentioned above. To be more precise, its aim is to answer questions concerning interpolation and amalgamation properties in varieties of equivalential algebras, particularly in the variety determined by the purely equivalential fragment of INT.  相似文献   

14.
Joseph D. Sneed 《Erkenntnis》1989,30(1-2):207-224
This paper describes the way in which a certain representation of basic scientific knowledge can be coupled with traditional microeconomic analysis to provide an analysis of rational research planning or agenda setting in basic science. Research planning is conceived as a resource allocation decision in which resources are being allocated to activities directed towards the solution of basic scientific problems. A structuralist representation of scientific knowledge is employed to provide a relatively precise characterization of a basic scientific problem.The research reported here was partially supported by a grant from the EXXON Foundation.  相似文献   

15.
The essay undertakes to explore the possibilities of mutually fruitful dialogue between moral philosophy and ontology, in particular, the ontology of relations. The latter copes with the question of how relations relate, whereas moral philosophy often ignores the ontological implications of such crucial relations as love and interpersonality. The paper proceeds as follows. First, the ontology of relations is discussed. Second, various examples are analysed. From this, a conception of relation instantiation emerges, according to which to determine which relation actually obtains, one has to take into account (a) the context, (b) the specific content or meaning of the relation, and (c) some action or decision or mode of existence of the relata. This conception suggests that relation instantiation cannot be explained by a single formula. By the help of this conception, Hume's thesis of the identity of killing relations between human and nonhuman beings is questioned. Then, the relation of love is analysed. It is shown that love as a moral relation is perfectly explicable in terms of ontology. Moreover, its essence is best captured by the interrelation of the particulars, the relation of love as a universal, and by the relating action of the particulars. Finally, the alleged relation of universal fraternity (interpersonality as such), linking up each human being to all other human beings, is discussed.  相似文献   

16.
Two studies showed that adults' responses to questions involving the term or varied markedly depending upon the type of question presented. When presented with various objects (A's and B's) and asked to circle all things which are A or B subjects tended to circle A's as well as B's, whereas when asked to circle all the A's or B's subjects showed a relatively stronger tendency to circle one or the other. Moreover the nature of the sets of objects (As and Bs) influenced behavior as well. There was also evidence that the effects due to question wording or set type transferred.  相似文献   

17.
When the covariance matrix (p×P) does not satisfy the formal factor analysis model for m factors, there will be no factor matrix (p×m) such that =(-) is diagonal. The factor analysis model may then be replaced by a tautology where is regarded as the covariance matrix of a set of residual variates. These residual variates are linear combinations of discarded common factors and unique factors and are correlated. Maximum likelihood, alpha and iterated principal factor analysis are compared in terms of the manner in which is defined, a maximum determinant derivation for alpha factor analysis being given. Weighted least squares solutions using residual variances and common variances as weights are derived for comparison with the maximum likelihood and alpha solutions. It is shown that the covariance matrix defined by maximum likelihood factor analysis is Gramian, provided that all diagonal elements are nonnegative. Other methods can define a which is nonGramian even when all diagonal elements are nonnegative.A modified version of this paper forms part of a Ph.D. thesis submitted to the University of South Africa.Presently at the National Institute for Personnel Research, South Africa.  相似文献   

18.
Peter Baumann 《Erkenntnis》2004,61(2-3):415-428
There are many ordinary propositions we think we know. Almost every ordinary proposition entails some lottery proposition which we think we do not know but to which we assign a high probability of being true (for instance:I will never be a multi-millionaire entails I will not win this lottery). How is this possible – given that some closure principle is true? This problem, also known as the Lottery puzzle, has recently provoked a lot of discussion. In this paper I discuss one of the most promising answers to the problem: Stewart Cohens contextualist solution, which is based on ideas about the salience of chances of error. After presenting some objections to it I sketch an alternative solution which is still contextualist in spirit.  相似文献   

19.
Summary In research on visual search within a single eye-fixation a number of different tasks are used and referred to interchangeably. Research with other types of tasks suggests that there are possibly important differences between these tasks. In the present study, two types of search tasks were compared under conditions as equal as possible: the go-no go task and the yes-no task. Conditions of low and high target-noise similarity were used. The results obtained showed: a) a steeper slope of the array size function in yes-no tasks than in go-no go tasks on the first day of practice but not on the second: b) a higher intercept value of the same function for yes-no tasks than for go-no go tasks; and c) a greater proportion of errors with yes-no tasks than with comparable go-no go tasks. A tentative model, describing the main features of the results obtained, is briefly sketched.  相似文献   

20.
On–off phenomena in Parkinson's disease (PD) are unpredictable motor fluctuations associated with long-term levodopa use. Mood fluctuations have been found to coincide with the motor fluctuations in that depression and anxiety increase while the person with PD is in the off state. What has been relatively unexplored is whether those persons with PD who have on–off phenomena differ psychologically in fundamental ways from those who do not have on–off phenomena. In the present study, depression and anxiety symptoms were assessed in 36 persons with PD (n = 14 with on–off phenomena, n = 22 without on–off phenomena). All those with on–off phenomena were assessed in their on state. Those persons with PD with on–off phenomena had significantly higher levels of anxiety than those without on–off phenomena. However, both groups, regardless of on–off status, were mildly depressed. Neurobiological interpretations of the results implicate the locus coeruleus in the pathogenesis of both on–off phenomena and anxiety, whereas psychological interpretations of the results involve the issues of learned helplessness and control over health symptoms in PD.  相似文献   

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