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1.
Z. Ziemba 《Studia Logica》1962,13(1):235-235
Summary The article attempts to give an answer to the question: why for the acceptance of a statementz 2 implied by another,z 1, it is required not only thatz 1 be true but also justified? The application in a given case of the rule allowing to accept a statement implied by another true one is not possible without establishing in an appropriate manner that the statement is true. Practically, therefore, we have to rely in the conditions for the acceptance of a statementz 2 implied by anotherz 1 on the manner of acceptance ofz 1. If we require that this manner of acceptance should guarantee the truth ofz 1, no special requirement of the truth ofz 1 is necessary. If the acceptance ofz 2 implied byz 1 depends onz 1 being accepted in a manner which does not ensure the truth ofz 1 (e. g. by induction), then we have to give up the requirement of the truth ofz 1. At most, we may prohibit the acceptance ofz 2 implied byz 1, inductively justified, if the evidence for the negation ofz 1 is better than the inductive one forz 1.  相似文献   

2.
Professor Ryszard Wójcicki once asked whether the degree of maximality of the consequence operationC determined by the theorems of the intuitionistic propositional logic and the detachment rule for the implication connective is equal to \(2^{2^\aleph 0} \) ? The aim of the present paper is to give the affirmative answer to the question. More exactly, it is proved here that the degree of maximality ofC Ψ — theΨ — fragment ofC, is equal to \(2^{2^\aleph 0} \) , for every such that → εΨ.  相似文献   

3.
The validity of a univocal multiple-choice test is determined for varying distributions of item difficulty and varying degrees of item precision. Validity is a function of d 2 + v 2 , where d measures item unreliability and v measures the spread of item difficulties. When this variance is very small, validity is high for one optimum cutting score, but the test gives relatively little valid information for other cutting scores. As this variance increases, eta increases up to a certain point, and then begins to decrease. Screening validity at the optimum cutting score declines as this variance increases, but the test becomes much more flexible, maintaining the same validity for a wide range of cutting scores. For items of the type ordinarily used in psychological tests, the test with uniform item difficulty gives greater over-all validity, and superior validity for most cutting scores, compared to a test with a range of item difficulties. When a multiple-choice test is intended to reject the poorestF per cent of the men tested, items should on the average be located at or above the threshold for men whose true ability is at theFth percentile.This research was performed under contract Nop 536 with the Bureau of Naval Personnel, and received additional support from the Bureau of Research and Service, College of Education, University of Illinois.  相似文献   

4.
The study of William Brown and William Stephenson, A Test of the Theory of Two Factors, is re-analyzed by means of the Thurstone multiple factor methods. No tests or correlations are left out of the original table of correlations as is done in the original analysis in an attempt to validate the two-factor theory. Space, verbal, and perceptual speed factors similar to those found by Thurstone, Wright, and Garrett are identified. A common factor of Maturation is postulated to account for the remaining communality of the tests. A fifth factor is considered to have no significance due to the small amount of variance which it contributes to the total.Master's Thesis, University of Chicago, Department of Psychology, 1939.  相似文献   

5.
6.
Experimental studies of the successive changes (frequently represented by curves describing laws of learning and other similar functional relationships) in a criterion variable accompanying experimental variations in a given treatment, and experimental comparisons of such changes for different populations or for different treatments, constitute a large and important class of psychological experiments. In most such experiments, no attempt has been made to analyze or to make allowance for errors of sampling or of observation. In many others, the techniques of error analysis that have been employed have been inefficient, inexact, or inappropriate. This paper suggests tests, using the methods of analysis of variance, of certain hypotheses concerning trends and trend differences in sample means obtained in experiments of this general type. For means of successive independent samples, tests are provided of the hypotheses: (H 1) that there is no trend, or that the trend is a horizontal straight line, (H 3) that there is a linear trend, (H 5) that the trend is as described by a line not derived from the observed means, and (H 7) that the trend is as described by a line fitted to the observed means. Tests are also provided of similar hypotheses (H 2,H 4,H 6, andH 8, respectively) for means of successive measurements of the same sample. Finally, tests are provided of the null hypotheses that there is no difference in trend in two series of means: (H 9) when each mean in each series is based on an independent sample, (H 10) when each pair of corresponding means is based on an independent sample, (H 11) when each series of means is based on an independent sample, and (H 12) when both series are based on a single sample.  相似文献   

7.
When the first of a uniform chain of neurones is excited with a stimulus intensityS 1, it is found that, according to the nature of the chain,either the excitation is always transmitted with decreasing intensity,or else the intensity for succeeding neurones of the chain approaches a fixed finite value, characteristic of the chain and independent ofS 1, wheneverS 1 exceeds a certain threshold value.  相似文献   

8.
Two logics L1 and L2 are negatively equivalent if for any set of formulas X and any negated formula ¬, ¬ can be deduced from the set of hypotheses X in L1 if and only if it can be done in L2. This article is devoted to the investigation of negative equivalence relation in the class of extensions of minimal logic.The author acknowledges support by the Alexander von Humboldt-StiftungPresented by Jacek Malinowski  相似文献   

9.
This research addresses the question: what is the risk of fall initiation at a certain human posture? There are postures from which no one is able to keep their balance and a fall will surely initiate (risk = 1), and others from which everyone may regain their stability (risk = 0). In other postures, only a portion of people can control their stability. One may interpret risk to chance of a fall to be initiated, and based on the portion of fallers assign a risk value to a given human posture (postural risk). Human posture can be mapped to a point in a 2-dimensional space: the x − v plane, the axes of which are horizontal components of the position and velocity of the center of mass of the body. For every pair of (x, v), the outcome of the balance recovery problem defines whether a person with a given strength level is able to regain their stability when released from a posture corresponding to that point. Using strength distribution data, we estimated the portion of the population who will initiate a fall if starting at a certain posture. A fast calculation approach is also introduced to replace the time-consuming method of solving the recovery problem many times. Postural risk of fall initiation for situations expressed by (x, v) pairs for the entire x − v plane is calculated and shown in a color-map.  相似文献   

10.
Hengxian, one of the bamboo books of the Chu State during the Warring States Period that is kept in the Shanghai Museum, was collected by the museum in 1994, and is an important piece of literature that discusses cosmic issues prior to Huainanzi. Based on Li Ling’s work on the text, as well as hermeneutic work by some other scholars, this essay represents another attempt to determine the words and meanings of the Hengxian, with a focus on its cosmological commentary. Translated by Huang Deyuan from Xi’an Jianzhu Keji Daxue Xuebao 西安建筑科技大学学报 (Journal of Xi’an University of Arch & Tech), 2007, (1): 1–8  相似文献   

11.
This article follows the development of Merleau-Ponty’s political philosophy from his 1947 text, Humanism and Terror, through a number of essays in the Adventures of the Dialectic, to the Preface to Signs published in 1959. It shows the process by which Merleau-Ponty escaped the “grip of marxism” as a philosophy of history. It notes the link between his philosophy of history and the concrete historical events of his times, particularly the Russian Revolution and its degeneration into Stalinism. It suggests a certain analogy between Merleau-Ponty’s reflection on the October Revolution and Kant’s reflection on the French Revolution. The notion of the universal class of the proletariat is the guiding thread in the analyses of both Merleau-Ponty’s proximity to marxism and the process by which he frees himself from its grip. We observe the role that this concept plays in Humanism and Terror and in the essays on Weber and Lukacs in the Adventure of the Dialectic where we eventually see its dissolution. It is argued that Merleau-Ponty arrives at a new conception of historical meaning which is neither totalizing or empiricist. The paper concludes by presenting an outline of the direction that his philosophy of history took after he extricated himself from marxism. This new philosophy took the form of a critical reflection on the role of the “notion of the hero” in 20th century political philosophy in general, particularly in Heidegger and Sartre.
Bernard FlynnEmail:
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12.
The central result of this paper provides a simple equational basis for the join, IRLLG, of the variety LG of lattice-ordered groups (-groups) and the variety IRL of integral residuated lattices. It follows from known facts in universal algebra that IRLLG=IRL×LG. In the process of deriving our result, we will obtain simple axiomatic bases for other products of classes of residuated structures, including the class IRL×s LG, consisting of all semi-direct products of members of IRL by members of LG. We conclude the paper by presenting a general method for constructing such semi-direct products, including wreath products.  相似文献   

13.
The author compared simulations of the “true” null hypothesis (z) test, in which ò was known and fixed, with the t test, in which s, an estimate of ò, was calculated from the sample because the t test was used to emulate the “true” test. The true null hypothesis test bears exclusively on calculating the probability that a sample distance (mean) is larger than a specified value. The results showed that the value of t was sensitive to sampling fluctuations in both distance and standard error. Large values of t reflect small standard errors when n is small. The value of t achieves sensitivity primarily to distance only when the sample sizes are large. One cannot make a definitive statement about the probability or “significance” of a distance solely on the basis of the value of t.  相似文献   

14.
The article is devoted to the systematic study of the lattice εN4 consisting of logics extending N4. The logic N4 is obtained from paraconsistent Nelson logic N4 by adding the new constant ⊥ and axioms ⊥ → p, p → ∼ ⊥. We study interrelations between εN4 and the lattice of superintuitionistic logics. Distinguish in εN4 basic subclasses of explosive logics, normal logics, logics of general form and study how they are relate. The author acknowledges support by the Alexander von Humboldt-Stiftung and by Counsil for Grants under RF President, project NSh - 2112.2003.1.  相似文献   

15.
Jürgen Humburg 《Topoi》1986,5(1):39-50
The aim of my book is to explain the content of the different notions of probability.Based on a concept of logical probability, which is modified as compared with Carnap, we succeed by means of the mathematical results of de Finetti in defining the concept of statistical probability.The starting point is the fundamental concept that certain phenomena are of the same kind, that certain occurrences can be repeated, that certain experiments are identical. We introduce for this idea the notion: concept K of similarity. From concept K of similarity we derive logically some probability-theoretic conclusions:If the events E() are similar —of the same kind - on the basis of such a concept K, it holds good that intersections of n of these events are equiprobable on the basis of K; in formulae: E(1)...E( n K E('1)...E(' n , i j ,' j ' j for ij On the basis of some further axioms a partial comparative probability structure results from K, which forms the starting point of our further investigations and which we call logical probability on the basis of K.We investigate a metrisation of this partial comparative structure, i.e. normed -additive functions m K, which are compatible with this structure; we call these functions m K measure-functions in relation to K.The measure-functions may be interpreted as subjective probabilities of individuals, who accept the concept K.Now it holds good: For each measure-function there exists with measure one the limit of relative frequencies in a sequence of the E().In such an event, where all measure-functions coincide, we speak of a quantitative logical probability, which is the common measure of this event. In formulae we have: l K (h n lim h n )=1 in words: There is the quantitative logical probability one that the limit of the relative frequencies exists. Another way of saying this is that the event * (hn lim h n) is a maximal element in the comparative structure resulting from K.Therefore we are entitled to introduce this limit and call it statistical probability P.With the aid of the measure-functions it is possible to calculate the velocity of this convergence. The analog of the Bernoulli inequation holds true: m K h n –P¦)1–1/4n2.It is further possible in the work to obtain relationships for the concept of statistical independence which are expressed in terms of the comparative probability.The theory has a special significance for quantum mechanics: The similarity of the phenomena in the domain of quantum mechanics explains the statistical behaviour of the phenomena.The usual mathematical statistics are explained in my book. But it seems more expedient on the basis of this new theory to use besides the notion of statistical probability also the notion of logical probability; the notion of subjective probability has only a heuristic function in my system.The following dualism is to be noted: The statistical behaviour of similar phenomena may be described on the one hand according to the model of the classical probability theory by means of a figure called statistical probability, on the other hand we may express all formulae by means of a function, called statistical probability function. This function is defined as the limit of the relative frequencies depending on the respective state of the universe. The statistical probability function is the primary notion, the notion of statistical probability is derived from it; it is defined as the value of the statistical probability function for the true unknown state of the universe.As far as the Hume problem, the problem of inductive inference, is concerned, the book seems to give an example of how to solve it.The developed notions such as concept, measure-function, logical probability, etc. seem to be important beyond the concept of similarity.The present work represents a summary of my book Grundzüge zu einem neuen Aufbau der Wahrscheinlich-keitstheorie [5], For this reason, I have frequently dispensed with providing proof and in this connection refer the interested reader to my book.  相似文献   

16.
The purpose of this study was to investigate the relative effectiveness of two methods of presenting visualized instruction to Ss and to determine the effectiveness of different types of visuals in facilitating S achievement of different educational objectives. Five hundred twenty Ss participated in the study; each received a pretest, participated in his respective instructional presentation, and received four criterial tests. Analysis indicated that (a) the method of presenting visualized instruction determines the type of visualization most effective in facilitating S achievement of different educational objectives; (b) for facilitating S achievement of certain objectives, color in visuals is an important instructional variable; and (c) not all visuals are equally effective in facilitating S achievement of different educational objectives.  相似文献   

17.
Background/ObjectiveEmerging adulthood (EA, age range between 18 to 29 years) is an important developmental stage that is characterized by marked social and psychological changes. Currently, its developmental features are quantified by the Inventory of the Dimensions of Emerging Adulthood (IDEA) but a validated Chinese version of this questionnaire (IDEA-C) is lacking. Thus, this research, which consists of two consecutive studies, aimed to investigate the psychometric properties of the translated IDEA in a Chinese sample of emerging adults.MethodFirstly, a forward-backward translation of the IDEA-C scale was conducted. Item analysis and exploratory factor analysis were performed in Sample 1a (n = 2438), followed by structural validity test in Sample 1b (n = 2461). Concurrent validity and internal consistency were evaluated in Sample 1(n = 4899). Finally, test-retest reliability was tested in Sample 2 (n = 185). Then, the second study aimed to test the factor structure proposed by study 1 in the non-student sample (n = 2200) by confirmatory factor analysis. In addition, the second study also investigated whether the attainment of college education influenced the EA experience of non-student emerging adults in China. And the association was examined between the socioeconomic status of emerging adults and the subscales of IDEA.ResultsIn the college sample, the IDEA-C scale presented a four-factor structure different from the original five-factor structure (χ2(190)=1116.84, p < 0.001; CFI = 0.97; TLI = 0.96; SRMR = 0.039; RMSEA = 0.050 [90%CI=0.047-0.052]). In addition, IDEA-C exhibited good internal consistency reliability (Cronbach's alpha >0.77), test-retest reliability (r>0.49, p < 0.01) and concurrent validity. And the CFA in non-student sample also showed an adequate fit indices (χ2(158) =710.10, p < 0.001, TLI=0.93, CFI=0.94, SRMR=0.038, RMSEA=0.04 [90%CI=0.037-0.040]) and an adequate internal consistency (Cronbach's alpha >0.64) and test-retest reliability (r>0.43, p < 0.01).ConclusionThe results of the present study confirmed that the Chinese version of the IDEA is found to be valid for measuring psychological characteristics of EA in Chinese-speaking samples of emerging adults.  相似文献   

18.
The reason for the emergence of consciousness of filial piety is that parental care could activate reciprocal filial piety. Parental care and filial piety are two supplementary phenomena caused by the same time consciousness. Phenomenology neglects consciousness of filial piety because it lacks the thinking that sees the fundamental “meaning of time” in the intersection of “past” and “future”. The consciousness of filial piety can only be really constituted by a human being’s personal experience. “Frustrations in personal life” and “breeding of children for oneself” are two occasions for an adult to fight against the separating effect of individualized consciousness and regain awareness of filial piety. Translated by Huang Deyuan from Beijing Daxue Xuebao 北京大学学报 (Journal of Peking University), 2006, (1): 14–24  相似文献   

19.
In this paper we consider the structure of the class FGModS of full generalized models of a deductive system S from a universal-algebraic point of view, and the structure of the set of all the full generalized models of S on a fixed algebra A from the lattice-theoretical point of view; this set is represented by the lattice FACSs A of all algebraic closed-set systems C on A such that (A, C) ε FGModS. We relate some properties of these structures with tipically logical properties of the sentential logic S. The main algebraic properties we consider are the closure of FGModS under substructures and under reduced products, and the property that for any A the lattice FACSs A is a complete sublattice of the lattice of all algebraic closed-set systems over A. The logical properties are the existence of a fully adequate Gentzen system for S, the Local Deduction Theorem and the Deduction Theorem for S. Some of the results are established for arbitrary deductive systems, while some are found to hold only for deductive systems in more restricted classes like the protoalgebraic or the weakly algebraizable ones. The paper ends with a section on examples and counterexamples. Dedicated to the memory of Willem Johannes Blok  相似文献   

20.
For each integer n ≥ 2, MVn denotes the variety of MV-algebras generated by the MV-chain with n elements. Algebras in MVn are represented as continuous functions from a Boolean space into a n-element chain equipped with the discrete topology. Using these representations, maximal subalgebras of algebras in MVn are characterized, and it is shown that proper subalgebras are intersection of maximal subalgebras. When A ∈ MV3, the mentioned characterization of maximal subalgebras of A can be given in terms of prime filters of the underlying lattice of A, in the form that was conjectured by A. Monteiro. Mathematics Subject Classification (2000): 06D30, 06D35, 03G20, 03B50, 08A30. Presented by Daniele Mundici  相似文献   

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