Information Dynamics

Though we have access to a wealth of information, the main issue is always how to process the available information. How to make sense of all we observe and know. Just like the English alphabet: we know there are 26 letters but unless we put these letters together in a meaningful way, they convey no information. There are infinitely many ways of putting these letters together. Only a small number of those make sense. Only some of those convey exactly what we wish to convey though the message may be interpreted differently by different individuals. That same issue comes up with information: how can we process the information we have? How can we infer and reason under conditions of incomplete observed information? In his seminal book on the philosophy of information, Floridi (2011a) raises a number of open questions. I discuss here one of these questions. That question is how to process information. To do so, I take the more realistic view that information is always limited, incomplete and possibly noisy. I define types of information, relate it to Floridi’s definitions and discuss a basic formulation for processing information under a unified framework. I relate it to some of the basic concepts discussed in the book.     

The Logic of Knowledge and the Flow of Information

In this paper I look at Fred Dretske’s account of information and knowledge as developed in Knowledge and The Flow of Information. In particular, I translate Dretske’s probabilistic definition of information to a modal logical framework and subsequently use this to explicate the conception of information and its flow which is central to his account, including the notions of channel conditions and relevant alternatives. Some key products of this task are an analysis of the issue of information closure and an investigation into some of the logical properties of Dretske’s account of information flow.     

Annotated Logic Applications for Imperfect Information

Imperfect information is a very general term that comprises different types of information, such as uncertain, vague, fuzzy, inconsistent, possibilistic, probabilistic, partially or totally incomplete information [2]. In the literature of knowledge representation we find a different formal model for each one of these distinct types. For example, annotated logic is a formal model to represent inconsistent information.Annotated logics are non-classical logics introduced in [20] as a logic programming theory. They were proved to be paraconsistent. Based on [5], we present in this work the annotated logic programming theory and some of its applications in Artificial Intelligence (AI). We present it as a formalism to reason with inconsistent information and investigate its possibility to represent other types of imperfect information, such as possibilistic and non-monotonic reasoning. Our main goal is to verify and confirm the importance of annotated logics as a tool for developing knowledge-based and automated reasoning systems in AI.     

Logic and Computational Complexity for Boolean Information Retrieval

We study the complexity of query satisfiability and entailment for the Boolean information retrieval models WP and AWV using techniques from propositional logic and computational complexity. WP and AWV can be used to represent and query textual information under the Boolean model using the concept of attribute with values of type text, the concept of word, and word proximity constraints. Variations of WP and AWP are in use in most deployed digital libraries using the Boolean model, text extenders for relational database systems (e.g., Oracle 10g), search engines, and P2P systems for information retrieval and filtering     

用逻辑和篇章知识来约束模板匹配——逻辑结构和篇章结构知识在信息抽取中的运用

本文以文献[2 ]的语料为主要对象,讨论语句的逻辑结构和篇章结构怎样约束信息模板的类型,并约束对当前句中缺失的或以代词等形式表达的信息项目的求解。首先说明什么是基于论元结构的逻辑结构和篇章结构知识,然后分析否定算子、时体成分怎样改变事件的类型及其跟有关事件模板的匹配关系。接着,讨论动词的论元结构的内嵌和名词化等句法操作,怎样造成有关论元及相应的信息项目的分布位置发生变化。最后,讨论怎样利用篇章结构知识来求解本句中缺失的或以代词、指示词形式表达的信息项目。     

用于不完全信息数据库的多值逻辑研究

1引言 自20世纪70年代末以来,用多值逻辑处理空值问题已成为数据库理论的一个重要研究方向[1～3].不完全信息数据库中引入多值逻辑(MVL)的研究是和空值的语义有关的.数据库中引起信息缺失的原因有十几种,根据语义可分成三种类型:不存在型空值、存在型空值和占位型空值.若在空值的处理中,这三种解释都采用,不作简化,这将导致七值逻辑(7VL).     

Markov逻辑网及其在信息抽取中的应用

介绍Markov逻辑网的理论模型,阐述Markov逻辑网的结构和参数学习算法及2种基本类型的推理,从命名实体识别、实体关系抽取和实体解析3个方面总结Markov逻辑网在信息抽取中的应用现状。分析结果表明,Markov逻辑网模型能较好地将一阶谓词逻辑和概率图模型相结合,灵活地在Markov网中融入模块化知识,描述复杂的特征。     

Information and Dynamics: Sequences of Call Markets

This paper is part of a wider research project with the objective of creating computational testbeds for designing and testing new mechanisms—new economic and political institutions. Here we illustrate the power of such an approach by testing two call market designs in a repeated demand-supply environment. We find there to be significant differences in performance depending on the information provided to the traders between calls. In particular, we find that both dynamic and static performance is better, less volitility and higher gains from trade, if traders receive less information between calls.     

Evolutionary Synthesis of Logic Circuits Using Information Theory

In this paper, we propose the use of Information Theory as thebasis for designing a fitness function for Boolean circuit designusing Genetic Programming. Boolean functions are implemented byreplicating binary multiplexers. Entropy-based measures, such asMutual Information and Normalized Mutual Information areinvestigated as tools for similarity measures between the targetand evolving circuit. Three fitness functions are built over aprimitive one. We show that the landscape of Normalized MutualInformation is more amenable for being used as a fitness functionthan simple Mutual Information. The evolutionary synthesizedcircuits are compared to the known optimum size. A discussion ofthe potential of the Information-Theoretical approach is given.     

领域值信息表上的邻域逻辑及其数据推理

引入了一种基于邻域值信息表的邻域逻辑,它是用邻域拓扑内点和邻域拓扑闭包作为逻辑算子的一种逻辑。其内点和闭包是先经二元关系定义了邻域系统,然后用这种邻域系统来定义它。这种逻辑被定义在信息表上,其表上的每个个体关于属性不是取单独一个值,而是扩充到取一个值的领域。公式的真值被扩充为一个区间或邻域,因此讨论一个公式可满足性的三种类型：邻域内点可满足、邻域闭包可满足和邻域可满足,即将公式的真值扩充为多值,并讨论了这种真值关于逻辑联结词的运算和公式的语义模型。最后还给出了这种逻辑的数据推理。     

模糊逻辑在数据库信息检索中的应用研究

模糊逻辑在传统信息检索中已有较多的研究,在数据库信息检索中引入模糊逻辑也引起越来越多的关注.使用隶属函数表示数据库中存在的语义不确定性和不精确性,建立相应的模糊索引,并采用模糊推理机制,同时融合对象级别的信息检索方法,可以有效提高数据库信息检索的效果.首先介绍模糊逻辑在传统信息检索中的应用及其优缺点,然后重点介绍模糊逻辑在数据库信息检索中的应用,最后探讨了基于模糊逻辑的关系数据库对象级别信息检索方法.     

打印信息防伪认证的一种逻辑签署技术及应用

为了防范对打印信息的伪造、篡改及非法使用,提出了一种逻辑签署技术,设计并实现了基于该技术的防伪认证系统,通过完整的逻辑体系保证其密码学意义上的高安全性,使得打印信息的检验过程快速、便利、精准和实用。该系统是一个开放的不受具体物理设备限制的体系,突破了现有打印信息防伪认证技术的模式。     

Practical Handling of Exception-Tainted Rules and Independence Information in Possibilistic Logic

This paper provides a survey of possibilistic logic as a simple and efficient tool for handling nonmonotonic reasoning, with some emphasis on algorithmic issues. In our previous works, two well-known nonmonotonic systems have been encoded in the possibility theory framework: the preferential inference based on System P, and the rational closure inference proposed by Lehmann and Magidor which relies on System P augmented with a rational monotony postulate. System P is known to provide reasonable but very cautious conclusions, and in particular, preferential inference is blocked by the presence of irrelevant properties. When using Lehmann's rational closure, the inference machinery, which is then more productive, may still remain too cautious, or on the contrary, provide counter -intuitive conclusions. The paper proposes an approach to overcome the cautiousness of System P and the problems encountered by the rational closure inference. This approach takes advantage of (contextual) independence assumptions of the form: the fact that is true (or is false) does not affect the validity of the rule normally if then . The modelling of such independence assumptions is discussed in the possibilistic framework. Moreover, we show that when a counter-intuitive conclusion of a set of defaults can be inferred, it is always possible to repair the set of defaults by adding suitable information so as to produce the desired conclusions and block unsuitable ones.     

The Information Dynamics of the Diffusion Processes of Population Genetics

With no prior knowledge assumed, the Wright-Fisher-Kimura diffusion process on gene frequency space is introduced and discussed from the geometric symmetries point of view. This derives from consideration of the covariance matrix of this diffusion as dynamical information analogous to Mahalonobis' static covariance matrix for informational discrimination of data in statistics. This model allows one to obtain Antonelli's ray solution in closed form for all dimensions of the gene frequency space, and to study the more difficult Felsenstein natural selection diffusion in higher dimensions. Of particular interest are the effects of positive and negative curvature in various regions of the frequency space. For the first time, several computer generated 3-dimensional geometries are presented in the collection of figures for the Felsenstein process of 3 alleles. Regions of negative curvature exhibit weak chaos in natural selection, while those of positive curvature exhibit meandering paths. An open problem is stated at the end.