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1.
A data integration system provides the user with a unified view, called global schema, of the data residing at different sources. Users issue their queries against the global schema, and the system computes answers to queries by suitably accessing the sources, through the mapping, i.e., the specification of the relationship between the global schema and the sources. Since sources are in general autonomous subsystems, the information provided by the data at the sources and the mapping is likely not to be consistent with the knowledge expressed by the global schema. Therefore, the question arises of how to interpret user queries in such a situation, i.e., in the presence of data contradicting the global schema and the mapping. In this paper, we provide an in-depth analysis of the problem of dealing with inconsistencies in data integration systems. In this respect, we highlight the central role played by the mapping, and propose a general “mapping-centered” semantics that allows for computing significant answers to user queries even in the presence of inconsistent information. Based on such a semantic analysis, we define a general formal framework for data integration. Then, we argue that our semantic approach formalizes a very reasonable way of handling inconsistency in such systems, since practically all the existing proposals in the literature can be reconstructed in our framework. This allows for comparing and evaluating the different existing proposals.  相似文献   

2.
We propose a functional view of ontologies that emphasises their role in determining answers to queries, irrespective of the formalism in which they are written. A notion of framework is introduced that captures the situation of a global language into which both an ontology language and a query language can be translated, in an abstract way. We then generalise existing notions of robustness from the literature, and relate these to interpolation properties that support modularisation of ontologies.  相似文献   

3.
Using a modified reception paradigm, normal and learning-disabled children were required to solve unidimensional, disjunctive, or conditional connectives under standard attending or enforced attending instructions. The major result was that enforced attending procedures facilitated solution of disjunctive and conditional concepts for normal children, while having minimal effects on rule attainment for the disabled. Within Sternberg's (1979) model, a number of subcomponent analyses were made on attribute combinations (e.g., TT, TF...), but only in the FF instance was there a difference between instructional conditions. Disabled were deficient in TT, TF, FF instances regardless of attending instructions. Results support a “reductive coding deficiency” in that learning-disabled children were unable to effectively utilize attentional instructions to encode certain attribute combinations.  相似文献   

4.
5.
Are there disjunctive properties? This question is important for at least two reasons. First, disjunctive properties are invoked in defense of certain philosophical theories, especially in the philosophy of mind. Second, the question raises the prior issue of what counts as a genuine property, a central concern in the metaphysics of properties. I argue here, on the basis of general considerations in the metaphysics of properties, that there are no disjunctive properties. Specifically, I argue that genuine properties must guarantee similarity‐in‐a‐respect among their instances, and must inhere in their bearers (two notions to be clarified). Disjunctive properties would fail both requirements. I compare the case of disjunctive properties with “mere Cambridge properties,” determinable properties, and functional properties, and show how my conception of properties remains compatible with determinables and functional properties while ruling out disjunctive and mere Cambridge properties.  相似文献   

6.
The adaptation of vocabulary between communication partners, i.e. the lexical entrainment phenomenon, is well documented. This study investigates whether the phenomenon can also be found in computer‐mediated communication between experts and laypersons. The respondents, who are medical experts (n = 46), answered to fictitious patients' queries on health problems. Language technicality within patients' queries was manipulated. One version contained certain concepts in everyday language, the other in technical language. Do experts adapt the vocabulary in their replies to that in the inquiry? Detailed analyses provide evidence that experts not only use the inquiry vocabulary, but also adapt the content of their answers to the technicality of the inquiry. Surprisingly, though queries differ in the use of vocabulary experts attributed very similar prior knowledge to the fictitious patient while providing them with very different replies. The results are discussed with respect to the implications for health counselling and for theoretical assumptions about adaptation in net‐based discourse. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   

7.
Admissible probability measurement procedures utilize scoring systems with a very special property that guarantees that any student, at whatever level of knowledge or skill, can maximize his expected score if and only if he honestly reflects his degree-of-belief probabilities. Section 1 introduces the notion of a scoring system with the reproducing property and derives the necessary and sufficient condition for the case of a test item with just two possible answers. A method is given for generating a virtually inexhaustible number of scoring systems, both symmetric and asymmetric, with the reproducing property. A negative result concerning the existence of a certain subclass of reproducing scoring systems for the case of more than two possible answers is obtained. Whereas Section 1 is concerned with those instances in which the possible answers to a query are stated in the test itself, Section 2 is concerned with those instances in which the student himself must provide the possible answer(s). In this case, it is shown that a certain minor modification of a scoring system with the reproducing property yields the desired admissible probability measurement procedure.The research reported in this paper was, in part, performed at the Decision Sciences Laboratory in support of Project 4690, Information Processing in Command and Control and, in part, sponsored by the Air Force Systems Command Electronic Systems Division, Decision Sciences Laboratory, under Contract No. AF 19(628)-4304, with ARCON Inc. This report is identified as ESD-TR-65-567. Further reproduction is authorized to satisfy the needs of the U. S. Government.  相似文献   

8.
Syntax precedes truth-theoretic semantics when it comes to understanding a logical constant. A constant in a language is logical iff its sense is entirely constituted by certain deductive rules. To be sense-constitutive, deductive rules governing a constant must meet certain conditions; those that do so are sense-constitutive by virtue of understanders' conditional dispositions to feel compelled to accept certain formulae. Acceptance is a cognitive formula-attitude. Since acceptance requires understanding, and a formula can contain more than one occurrence of logical constants, this account involves a 'local holism', but no circularity. I argue that no logical constant is ambiguous between a classical and a constructive sense; but I allow that one constant may have distinct classical and constructive 'semantic values'. A logical constant's sense helps to determine its semantic value, but only together with certain constraints on satisfaction and frustration; it seems that the latter must include 'convention T'-style schemata.  相似文献   

9.
余达祥  胡竹菁 《心理科学》2001,24(6):694-697
本文探讨THOG问题的演绎结构及其非Wason-Brooks判断方法,据于Wason-Brooks判断程序和THOG问题逻辑结构的分析导致如下结论:1.Wason-BrooksTHOG判定方法并非判定THOG的唯一方法;2、被试选择那一种演绎判定模式取决于被试如何对原问题进行等效表征转换;3.判断失败可能意味着被试存在短时记忆容量障碍或者等效表征转换障碍。  相似文献   

10.
Are there any disjunctive properties—features of things such as being either red or round, or Nelson Goodman’s infamous example of being grue (i.e. either green if observed on or before 2500 A.D. or blue otherwise)? As esoteric as the question may seem at first, central issues about the metaphysics of properties hinge upon its answer, such as whether reductive views about special science properties can handle the phenomenon of multiple realizability. A familiar argument for a negative answer is that disjunctive properties fail to guarantee that their instances are similar in some genuine respect. In this paper, I respond to a novel, sophisticated version of this argument developed in recent work by Paul Audi. Along the way, I develop two new accounts of what it is for a property to be disjunctive—which rely on important recent work on the nature of essence and analysis—and clarify what one is committed to in believing that there are any disjunctive properties at all.  相似文献   

11.
This article presents a unified theory of human reasoning. The goal of the theory is to specify what constitutes reasoning, as opposed to other psychological processes, and to characterize the psychological distinction between inductive and deductive reasoning. The theory views reasoning as the controlled and mediated application of three processes— selective encoding, selective comparison, and selective combination—to inferential rules. The first two of these processes are essentially inductive in nature; the third is essentially deductive. The theory describes these three processes, specifies the kinds of inferential rules and their use in several reasoning tasks, and specifies the mediators that affect how well the processes can be applied to the rules. The theory is shown to apply to a variety of reasoning tasks and is compared to other theories as well.  相似文献   

12.
The authors present a structural analysis of three spatial diagrams-matrices, networks, and hierarchies-that specifies 10 properties on which these diagrammatic representations are hypothesized to differ: global structure, building block, number of sets, item/link constraints, item distinguishability, link type, absence of a relation, linking relations, path, and traversal. Each property has a "value" for each diagram, and these property values constitute the applicability conditions for the representations. Twenty-three college students (computer science majors and math educators) selected the type of diagram they thought would be most efficient for organizing the information in each of 18 short scenarios and verbally justified the reasons for their selections. The verbal protocols were coded with respect to the structural analysis. Both the representation selection and verbal justification data provided strong support for the structural analysis. Additionally, a factor analysis of students' justifications indicated that the organization of their knowledge is consistent with the structural analysis. Students' use of the structural properties to select appropriate representations and to justify those selections indicates that the structural analysis has psychological force.  相似文献   

13.
Ibens  Ortrun 《Studia Logica》2002,70(2):241-270
Automated theorem proving amounts to solving search problems in usually tremendous search spaces. A lot of research therefore focuses on search space reductions. Our approach reduces the search space which arises when using so-called connection tableau calculi for first-order automated theorem proving. It uses disjunctive constraints over first-order equations to compress certain parts of this search space. We present the basics of our constrained-connection-tableau calculi, a constraint extension of connection tableau calculi, and deal with the efficient handling of constraints during the search process. The new techniques are integrated into the automated connection tableau prover Setheo.  相似文献   

14.
Research on probability judgment has traditionally emphasized that people are susceptible to biases because they rely on “variable substitution”: the assessment of normative variables is replaced by assessment of heuristic, subjective variables. A recent proposal is that many of these biases may rather derive from constraints on cognitive integration, where the capacity-limited and sequential nature of controlled judgment promotes linear additive integration, in contrast to many integration rules of probability theory (Juslin, Nilsson, & Winman, 2009). A key implication by this theory is that it should be possible to improve peoples’ probabilistic reasoning by changing probability problems into logarithm formats that require additive rather than multiplicative integration. Three experiments demonstrate that recasting tasks in a way that allows people to arrive at the answers by additive integration decreases cognitive biases, and while people can rapidly learn to produce the correct answers in an additive formats, they have great difficulty doing so with a multiplicative format.  相似文献   

15.
We introduce two new belief revision axioms: partial monotonicity and consequence correctness. We show that partial monotonicity is consistent with but independent of the full set of axioms for a Gärdenfors belief revision sytem. In contrast to the Gärdenfors inconsistency results for certain monotonicity principles, we use partial monotonicity to inform a consistent formalization of the Ramsey test within a belief revision system extended by a conditional operator. We take this to be a technical dissolution of the well-known Gärdenfors dilemma.In addition, we present the consequential correctness axiom as a new measure of minimal revision in terms of the deductive core of a proposition whose support we wish to excise. We survey several syntactic and semantic belief revision systems and evaluate them according to both the Gärdenfors axioms and our new axioms. Furthermore, our algebraic characterization of semantic revision systems provides a useful technical device for analysis and comparison, which we illustrate with several new proofs.Finally, we have a new inconsistency result, which is dual to the Gärdenfors inconsistency results. Any elementary belief revision system that is consequentially correct must violate the Gärdenfors axiom of strong boundedness (K*8), which we characterize as yet another monotonicity condition.This work was supported by the McDonnell Douglas Independent Research and Development program.  相似文献   

16.
Tucker's three-mode common factor analysis is used to explore the intrinsic individual differences in a figural, disjunctive conceptual behavior task. The results reveal differential shifts in the structure of the individual differences during concept identification. Individual patterns can be described by five factors, each of which specifies the parameter vales for the shape of the individual performance functions. A three-way core further identifies the nature of the individual differences factors. These results indicate that averaged curves for the separate response measures would not have adequately reflected the individual data in this sample. The present findings are consistent with earlier work and suggest that a better approach to the study of complex human behavior is to identify the individual differences intrinsic to the situation before mapping antecedent influences on the dimensionality of the behavior.  相似文献   

17.
In previous work with adults (A. Koriat & M. Goldsmith, 1994, 1996c), it was shown that people can enhance the accuracy of their testimony substantially when they (a) are effective in monitoring the correctness of their answers, (b) are free to control their reporting accordingly (i.e., to decide which pieces of information to volunteer and which to withhold), and (c) are given incentives for accurate reporting. A theoretical model was developed, which specifies the critical role of metacognitive monitoring and control processes in mediating free-report memory accuracy. The present study applies that model to examine the strategic regulation of memory accuracy by children. Three experiments indicate that both younger (ages 7 to 9) and older (ages 10 to 12) children can enhance the accuracy of their testimony by screening out wrong answers under free-report conditions but suggest a developmental trend in the level of memory accuracy that is thereby achieved. The implications of the results for the dependability of children's testimony in legal settings are discussed.  相似文献   

18.
Information associated with the inertia tensor is the preeminent explanation for haptic perception of object properties, notably wielded rod length. Critics counter that tensorial-based information requires non-tensorial supplementation (mass, torque). However, those critiques omit important constraints. With relevant constraints included, the inertia tensor alone completely specifies rod length. I list constraints inherent (but tacit) in haptic rod length perception, and show that object properties associated with the inertia tensor are invariant, even with constraints removed, by involving (a) longitudinal moment equivalents for rod mass and (b) derivatives of moments with respect to varying rotation axes. Analytic outcomes show tensorial-based information is a robust basis for wielded rod length perception, and suggest open questions for empirical exploration.  相似文献   

19.
Kovacs  David Mark 《Synthese》2021,198(9):8933-8953

According to Humeanism about the laws, the laws of nature are nothing over and above certain kinds of regularities about particular facts (the “Humean mosaic”). Humeanism has often been accused of circularity: according to scientific practice laws often explain their instances, but on the Humean view they also reduce to the mosaic, which includes those instances. In this paper I formulate the circularity problem in a way that avoids a number of controversial assumptions routinely taken for granted in the literature, and against which many extant responses are therefore ineffective. I then propose a solution that denies the alleged Humean commitment that laws are explained by their instances. The solution satisfies three desiderata that other solutions don’t: it provides independent motivation against the idea that Humean laws are explained by their instances; it specifies the sense in which Humean laws are nonetheless “nothing over and above” their instances; and it gives an alternative account of what does explain the laws, if not their instances. This solution, I will argue, is not only the simplest but also the oldest one: it appeals only to tools and theses whose first appearance predates the earliest statements of the circularity problem itself.

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20.
John Mumma 《Synthese》2010,175(2):255-287
Though pictures are often used to present mathematical arguments, they are not typically thought to be an acceptable means for presenting mathematical arguments rigorously. With respect to the proofs in the Elements in particular, the received view is that Euclid’s reliance on geometric diagrams undermines his efforts to develop a gap-free deductive theory. The central difficulty concerns the generality of the theory. How can inferences made from a particular diagrams license general mathematical results? After surveying the history behind the received view, this essay provides a contrary analysis by introducing a formal account of Euclid’s proofs, termed Eu. Eu solves the puzzle of generality surrounding Euclid’s arguments. It specifies what diagrams Euclid’s diagrams are, in a precise formal sense, and defines generality-preserving proof rules in terms of them. After the central principles behind the formalization are laid out, its implications with respect to the question of what does and does not constitute a genuine picture proof are explored.  相似文献   

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