KNOWLEDGE ENGINEERING the Applied Side of Artificial Intelligence

Total Page:16

File Type:pdf, Size:1020Kb

KNOWLEDGE ENGINEERING the Applied Side of Artificial Intelligence Stanford Heuristics Programming Project September 1980 Report No. HPP-80-21 Department of Computer Science Report No. STAN-CS-80-812 KNOWLEDGE ENGINEERING The Applied Side of Artificial Intelligence by Edward A. Feigenbaum Research sponsoredby Office of Naval Research DEPARTMENT OFCOMPUTER SCIENCE Stanford University Knowledge Engineering: The Applied Side of Artificial Intelligence Edward A. Feigenbaum Computer Science Department Stanford University * Stanford, California 94305 Copyright (c) l9Bo Edward A. Feigenbaum ALL RIGHTS RESERVED ■: -» «. Knowledge Engineering: The Applied Side of Artificial Intelligence Edward A. Feigenbaum Computer Science Department Stanford University Stanford, CA USA 94305 1.0 Introduction: Symbolic Computation and Inference This paper will discuss the applied artificial intelligence work that is sometimes called "knowledge engineering". The work is based on computer programs that do symbolic manipulations and symbolic inference, not calculation. The programs I will discuss do essentially no numerical qualitative calculation. They discover lines-of-reasoning leading to solutions to problems stated symbolically. 1.1 Knowledge Since in this paper I often use the term "knowledge", let me say what I mean by it. The knowledge of an area of expertise—of a field of practice—is generally of two types: a) Facts of the domain—the widely shared knowledge that is written in textbooks, and in journals of a field; that constitutes the kind of professor material that a would lecture about in a class, b) Equally as important to the practice of a field is the heuristic knowledge—knowledge which constitutes the rules of expertise, the rules of good practice, the judgmental rules of the field, the rules of plausible reasoning. These rules collectively constitute what the mathematician, George Polya, has called the "art of good guessing". In contrast to the facts of the field, its rules of expertise, its rules of good guessing, are rarely written down. This knowledge is transmitted in internships, Ph.D. programs, apprenticeships. The programs I will describe require, for expert performance on problems, heuristic knowledge to be combined with the facts of the discipline. 1.2 Expert Systems The act of obtaining, formalizing and putting to work these kinds of rules is what we call "expertise modeling". In the modeling of expertise, we construct programs called "expert systems". The goal of an "expert system" project is to write a program that achieves a high level of performance on problems that are difficult enough to require significant human expertise for their solution. The more common strategy of AI research is to choose a highly simplified problem— sometimes called, a "toy problem"—and exploit the toy problem in depth. In the problems we contrast, choose require the expertise of an M.D., or a Ph.D., or at least a very highly trained, specialist in a field, to solve. An expert system of this type consists of only two things: a base, an knowledge and inference procedure. The knowledge base contains the facts and heuristics; the * inference procedure consists of the processes that work over the knowledge base infer to solutions to problems, to do analyses, to form hypotheses, etc. In principle, the knowledge base is separable from the inference procedure. 1.3 The Scientific Issues Underlying Knowledge Engineering What are the central scientific issues of the Artificial Intelligence field from which this more applied research draws its inspiration? I'd like to categorize these under three headings. field* repreL^S «** the of the *?. **»*«*>«S can be-conveniently acces^ for probl^sol^ngT^ C<>m^tet' ° they inference engine. L f ei^TS ULSJ** ° poss^e't^lc^e^^iege L^rtant foVf^sW5^ *?" IS of^fS^^^ -Mr-a^sra^ f intelligence. For a long^ rtificial ° was cloaked uX^^rd^Sf,the word "learning".? able to be more precise ahnnh ?h» ZtltS , Now£ we are increased P-isionKme^w^ -* this . diligence research" £ SSJW^J* *£ X 06 knowledge is powerf The of «'= Programs, power «S5 does^not^f^ f renC Procedure resides in the specifl^Se of orohl l »" systems Sf "V" " - we will ta building will I^%A^^^J?ZSSS? of means for mUSt haVe more al*omatic «■ replacing what^s currenUv o^'^ procedure. The preblm time-consuming araJ expensive of knowledgeWled9e ««*»»tionacoulsitiofis the critical in Artificial Intelligence "° bottleneck problem 2.0 A Brief Tutorial Using the MVCIN Program As the basis of the exposition , of underlvina ideas T win , . *.«»uj.l* exogenous possibly infer). \ data the computer couldn't reaL^aS tfa^resul t"S tSKET dladSSff9nosis) \We can expect that it should be ableWIB touo exolainexplain " ' "^ tnathhati^!!lme-of-reasomna- to thp near t« p^~+. % v t " 2.1 Knowledge in MYCIN rod ctlon rule consists of an "if" part and a (sometimes calledTV !UC^ .P V " "then" part situation part" and "action part"). The "if part" defines a set of „=^ conditions of relevancy such that if each of these clauses is true, then the conclusion follows. (2) The rule is shown in approximately the way the expert would enter it; and exactly the way the doctor would see the rule if it were displayed This piece of knowledge will be evoked from the knowledge base if the conditions are true, and will be built into the line-of-reasoning. If: 1) The infection which requires therapy is meningitis, and 2) The type of the infection is fungal, and 3) Organisms were not seen on the stain of the culture, and 4) The patient is not a compromised host, and 5) The patient has been to an area that is endemic for coccidiomycoses, and 6) The race of the patient is one of: black asian indian, and 7) The cryptococcal antigen in the csf was not positive Then: there is suggestive evidence that cryptococcus is not one of the organisms which might be causing the infection. Figure 1: A piece of knowledge in MYCIN 2.2 Inexact Inference In MYCIN, there is a way for the expert to state to what extent, on a scale from 0.1 to 1.0, he believes that the preconditions imply the conclusion. 1.0 is definitional certainty; 0.9 is "very strong evidence"; 0.6 is "suggestive evidence"; and so on. These r indices are combined in MYCIN with a very- simple and easily function, explained yielding an index called a "cumulative certainty factor", an index of "strength of belief" in the line-of-reasoning. 2.3 MYCIN Diagnosis and Therapy Figure 2 shows a typical MYCIN diagnosis. Then MYCIN proceeds to conduct a shorter consultation with the physician about such things as the patient's known sensitivities to various types of antibiotics and the resistance shown by certain organisms to various kinds of antibiotics. MYCIN then produces a therapy recommendation such as shown in Figure 3. INFECTION-1 is MENINGITIS + <ITEM-1> E.COLI [from clinical evidence only] + <ITEM-2> PSEUDCMCNAS-AERLCINOSA [from clinical evidence only] + <ITEM^-3> KLEBSIELLA-PNEUMONIAE [from clinical evidence only] + <ITEM-4> DIPLCCOCCUS-PNEUMCNIAE [from clinical evidence only] Figure 2: An example of a MYCIN diagnosis 4 My preferred therapy recommendation is as follows: In order to cover for Items <1 2 3 4>: Give the following in combination: 1) AMPICILLIN Dose: 3.5g (28.0 ml) q4h IV [calculated on basis of 50 mg/kg] 2) GENTAMICIN Dose: 11 ing (3.0 ml, 80mg/2ml ampule) qSh IV [calculated on basis of 1.7 mg/kg] plus consider giving 5 mq q24h Intrathecal Comments: Monitor serum concentrations Since high concentrations of penicillins can inactivate aminoglycosides, do not mix these two antibiotics in the XV Dottle. same Figure 3: An example of a MYCIN antibiotic therapy recommendation 2.4 MYCIN'S Line-of-Reasoning MYCIN'S line-of-reasoning a is chain of rules that concludes the (oerhans uncertain) presence of an infecting organism from laboratory test data and W history. The line-of-reasoning is St discovered by backward cZUT. tt search^tarts Vari US P SSible rganianS aS "g aIS t0 be 5?data ° ° ° ° «*i^i uSSbTSS The explanation facility can exhibit selected portions of the requested by the user. It can chain as answer a variety of queries during or after the dialogue, such as: "Why (are you asking me for this information)?" consultation particular or "How some conclusion reached) ?"Che interesting form of query is shown in FwfT To answerit MYCIN must keep track of not only also the 9 invalid lines explored, along with reasonsacxre^^ll^Sr^S"^for unacceptability ' USER: WHY DIDN'T YOU GIVE TETRACYCLINE FOR E.COLI IN REC-1 MYCIN: TETRACYCLINE was discounted for ITEM-1 (RECQvIMENDATION-1 ) because there is evidence that this e.coli is not sensitive to it. Figure 4: An example of MYCIN'S explanation facility 2.5 MYCIN'S Inference Procedure We can remove the knowledge base of MYCIN and substitute a set of rules uivalent from ise^ *> saying that the knowledge base and the ITfTrtl.T^ rt SyStem ts cMIe ' «*£ infLtioSslisLse'dl a ddiSSEa<3nosls rules yields'VS an inference "engine"R^^ EMYCINYr (for,r^°r?c f? f MI * which we call " Essential Mycin or Empty Mycin or Engine Mycin). 3.0 Building a New System with the EMYCIN Tool: PUFF Combining with EMYCIN a set of rules for pulmonary function diagnosis (diagnosis eS) rod Ced a ?M^?, di^ostic program called PUFF (Osborn et al. In this diagnosticdlSe^ situation,-F " a patient 1979?? is breathing in and out of an instrument cailS a spirometer, producing measurements of flow of air in expiration and inhalation versus lung volume. Data reduction is done by a PDP-11, and data interpretation done by is PUFF. (3) The PUFF report is reviewed by an expert physician, is signed accurate, if put into the patient record and sent to the referring physician Currently, per about 85 cent of the PUFF outputs are signed without modification.
Recommended publications
  • Arxiv:1910.13561V1 [Cs.LG] 29 Oct 2019 E-Mail: [email protected] M
    Noname manuscript No. (will be inserted by the editor) A Heuristically Modified FP-Tree for Ontology Learning with Applications in Education Safwan Shatnawi · Mohamed Medhat Gaber ∗ · Mihaela Cocea Received: date / Accepted: date Abstract We propose a heuristically modified FP-Tree for ontology learning from text. Unlike previous research, for concept extraction, we use a regular expression parser approach widely adopted in compiler construction, i.e., deterministic finite automata (DFA). Thus, the concepts are extracted from unstructured documents. For ontology learning, we use a frequent pattern mining approach and employ a rule mining heuristic function to enhance its quality. This process does not rely on predefined lexico-syntactic patterns, thus, it is applicable for different subjects. We employ the ontology in a question-answering system for students' content-related questions. For validation, we used textbook questions/answers and questions from online course forums. Subject experts rated the quality of the system's answers on a subset of questions and their ratings were used to identify the most appropriate automatic semantic text similarity metric to use as a validation metric for all answers. The Latent Semantic Analysis was identified as the closest to the experts' ratings. We compared the use of our ontology with the use of Text2Onto for the question-answering system and found that with our ontology 80% of the questions were answered, while with Text2Onto only 28.4% were answered, thanks to the finer grained hierarchy our approach is able to produce. Keywords Ontologies · Frequent pattern mining · Ontology learning · Question answering · MOOCs S. Shatnawi College of Applied Studies, University of Bahrain, Sakhair Campus, Zallaq, Bahrain E-mail: [email protected] M.
    [Show full text]
  • Building Dialogue Structure from Discourse Tree of a Question
    The Workshops of the Thirty-Second AAAI Conference on Artificial Intelligence Building Dialogue Structure from Discourse Tree of a Question Boris Galitsky Oracle Corp. Redwood Shores CA USA [email protected] Abstract ed, chat bot’s capability to maintain the cohesive flow, We propose a reasoning-based approach to a dialogue man- style and merits of conversation is an underexplored area. agement for a customer support chat bot. To build a dia- When a question is detailed and includes multiple sen- logue scenario, we analyze the discourse tree (DT) of an ini- tences, there are certain expectations concerning the style tial query of a customer support dialogue that is frequently of an answer. Although a topical agreement between ques- complex and multi-sentence. We then enforce what we call tions and answers have been extensively addressed, a cor- complementarity relation between DT of the initial query respondence in style and suitability for the given step of a and that of the answers, requests and responses. The chat bot finds answers, which are not only relevant by topic but dialogue between questions and answers has not been thor- also suitable for a given step of a conversation and match oughly explored. In this study we focus on assessment of the question by style, argumentation patterns, communica- cohesiveness of question/answer (Q/A) flow, which is im- tion means, experience level and other domain-independent portant for a chat bots supporting longer conversation. attributes. We evaluate a performance of proposed algo- When an answer is in a style disagreement with a question, rithm in car repair domain and observe a 5 to 10% im- a user can find this answer inappropriate even when a topi- provement for single and three-step dialogues respectively, in comparison with baseline approaches to dialogue man- cal relevance is high.
    [Show full text]
  • Problem of Extracting the Knowledge of Experts Fkom the Perspective of Experimental Psychology
    AI Magazine Volume 8 Number 2 (1987) (© AAAI) The ‘Problem of Extracting the Knowledge of Experts fkom the Perspective of Experimental Psychology RobertR.Hoffman or perceptual and conceptual and represent their special knowledge The first step in the development of an problems requiring the skills of . [It] may take several months of the expert system is the extraction and charac- an expert, expertise is rare, the expert’s time and even more of the terization of the knowledge and skills of an expert’s knowledge is extremely system builder’s” (p. 264). Three years expert. This step is widely regarded as the detailed and interconnected, and our later, Duda and Shortliffe (1983) major bottleneck in the system develop- scientific understanding of the echoed this lament: “The identifica- ment process To assist knowledge engi- expert’s perceptual and conceptual tion and encoding of knowledge is one neers and others who might be interested in the development of an expert system, I processes is limited. Research on the of the most complex and arduous offer (1) a working classification of meth- skills of experts in any domain affords tasks encountered in the construction ods for extracting an expert’s knowledge, an excellent opportunity for both of an expert system” (p. 265). (2) some ideas about the types of data that basic and practical experimentation. Some common phrases that occur the methods yield, and (3) a set of criteria My investigations fall on the experi- in the literature are “knowledge acqui- by which the methods can be compared mental psychology side of expert sys- sition is the time-critical component” relative to the needs of the system develop- tem engineering, specifically the prob- (Freiling et al.
    [Show full text]
  • Towards Unsupervised Knowledge Extraction
    Towards Unsupervised Knowledge Extraction Dorothea Tsatsoua,b, Konstantinos Karageorgosa, Anastasios Dimoua, Javier Carbob, Jose M. Molinab and Petros Darasa aInformation Technologies Institute (ITI), Centre for Research and Technology Hellas (CERTH), 6th km Charilaou-Thermi Road, 57001, Thermi, Thessaloniki, Greece bComputer Science Department, University Carlos III of Madrid, Av. Universidad 30, Leganes, Madrid 28911, Spain Abstract Integration of symbolic and sub-symbolic approaches is rapidly emerging as an Artificial Intelligence (AI) paradigm. This paper presents a proof-of-concept approach towards an unsupervised learning method, based on Restricted Boltzmann Machines (RBMs), for extracting semantic associations among prominent entities within data. Validation of the approach is performed in two datasets that connect lan- guage and vision, namely Visual Genome and GQA. A methodology to formally structure the extracted knowledge for subsequent use through reasoning engines is also offered. Keywords knowledge extraction, unsupervised learning, spectral analysis, formal knowledge representation, symbolic AI, sub-symbolic AI, neuro-symbolic integration 1. Introduction Nowadays, artificial intelligence (AI) is linked mostly to machine learning (ML) solutions, enabling machines to learn from data and subsequently make predictions based on unidentified patterns in data, taking advantage of neural network (NN)-based methods. However, AI is still far from encompassing human-like cognitive capacities, which include not only learning but also understanding1, abstracting, planning, representing knowledge and logically reasoning over it. On the other hand, Knowledge Representation and Reasoning (KRR) techniques allow machines to reason about structured knowledge, in order to perform human-like complex problem solving and decision-making. AI foundations propose that all the aforementioned cognitive processes (learning, abstracting, representing, reasoning) need to be integrated under a unified strategy, in order to advance to In A.
    [Show full text]
  • Ontology and Information Systems
    Ontology and Information Systems 1 Barry Smith Philosophical Ontology Ontology as a branch of philosophy is the science of what is, of the kinds and structures of objects, properties, events, processes and relations in every area of reality. ‘Ontology’ is often used by philosophers as a synonym for ‘metaphysics’ (literally: ‘what comes after the Physics’), a term which was used by early students of Aristotle to refer to what Aristotle himself called ‘first philosophy’.2 The term ‘ontology’ (or ontologia) was itself coined in 1613, independently, by two philosophers, Rudolf Göckel (Goclenius), in his Lexicon philosophicum and Jacob Lorhard (Lorhardus), in his Theatrum philosophicum. The first occurrence in English recorded by the OED appears in Bailey’s dictionary of 1721, which defines ontology as ‘an Account of being in the Abstract’. Methods and Goals of Philosophical Ontology The methods of philosophical ontology are the methods of philosophy in general. They include the development of theories of wider or narrower scope and the testing and refinement of such theories by measuring them up, either against difficult 1 This paper is based upon work supported by the National Science Foundation under Grant No. BCS-9975557 (“Ontology and Geographic Categories”) and by the Alexander von Humboldt Foundation under the auspices of its Wolfgang Paul Program. Thanks go to Thomas Bittner, Olivier Bodenreider, Anita Burgun, Charles Dement, Andrew Frank, Angelika Franzke, Wolfgang Grassl, Pierre Grenon, Nicola Guarino, Patrick Hayes, Kathleen Hornsby, Ingvar Johansson, Fritz Lehmann, Chris Menzel, Kevin Mulligan, Chris Partridge, David W. Smith, William Rapaport, Daniel von Wachter, Chris Welty and Graham White for helpful comments.
    [Show full text]
  • Ontology to Appear in the Encyclopedia of Database Systems, Ling Liu and M
    Ontology to appear in the Encyclopedia of Database Systems, Ling Liu and M. Tamer Özsu (Eds.), Springer-Verlag, 2008. TITLE OF ENTRY Ontology BYLINE Tom Gruber, http://tomgruber.org. Formerly of Stanford University, Intraspect Software, and RealTravel.com. SYNONYMS computational ontology, semantic data model, ontological engineering DEFINITION In the context of computer and information sciences, an ontology defines a set of representational primitives with which to model a domain of knowledge or discourse. The representational primitives are typically classes (or sets), attributes (or properties), and relationships (or relations among class members). The definitions of the representational primitives include information about their meaning and constraints on their logically consistent application. In the context of database systems, ontology can be viewed as a level of abstraction of data models, analogous to hierarchical and relational models, but intended for modeling knowledge about individuals, their attributes, and their relationships to other individuals. Ontologies are typically specified in languages that allow abstraction away from data structures and implementation strategies; in practice, the languages of ontologies are closer in expressive power to first-order logic than languages used to model databases. For this reason, ontologies are said to be at the "semantic" level, whereas database schema are models of data at the "logical" or "physical" level. Due to their independence from lower level data models, ontologies are used for integrating heterogeneous databases, enabling interoperability among disparate systems, and specifying interfaces to independent, knowledge-based services. In the technology stack of the Semantic Web standards [1], ontologies are called out as an explicit layer. There are now standard languages and a variety of commercial and open source tools for creating and working with ontologies.
    [Show full text]
  • Innovations in Knowledge Engineering
    Innovations in Knowledge Engineering Editors Ravi Jain Australia Ajith Abraham U.S.A. Colette Faucher France Berend Jan van der Zwaag The Netherlands Foreword A research text book aims to provide a unique and long lasting statement about the current thinking in a given subject area. This book delivers exactly this in the area of knowledge engineering, i.e., the design and construction of systems that convert data into knowledge. Knowledge is fundamental to intelligent systems, it provides us with the stuff with which we are able to extend the abilities of our minds. It allows us to auto- matically assist humans to manage the world around us. It allows us to build a bet- ter world. Knowledge is gained from data and, as we are all too aware, the amount of data in all forms is growing at a faster rate every year. Unfortunately, this data is often unstructured, noisy, incomplete and uncertain, making our job all the more diffi- cult. Managing this data and turning it into knowledge is a vital endeavour. Unfor- tunately, the knowledge held in the data can be complex, dealing with this com- plexity is still unsolved. We desperately need well principled methods that can be used again and again to reliably engineer systems. Methods that can be applied by software engineers in their every day work to develop powerful systems that will really help people. Pro- viding methods to do this is exactly what this book is about. This book presents a wide range of methods that tackle these issues. It cannot hope to cover all of them, but the areas it has covered are important and timely.
    [Show full text]
  • Ontology for Information Systems (O4IS) Design Methodology Conceptualizing, Designing and Representing Domain Ontologies
    Ontology for Information Systems (O4IS) Design Methodology Conceptualizing, Designing and Representing Domain Ontologies Vandana Kabilan October 2007. A Dissertation submitted to The Royal Institute of Technology in partial fullfillment of the requirements for the degree of Doctor of Technology . The Royal Institute of Technology School of Information and Communication Technology Department of Computer and Systems Sciences IV DSV Report Series No. 07–013 ISBN 978–91–7178–752–1 ISSN 1101–8526 ISRN SU–KTH/DSV/R– –07/13– –SE V All knowledge that the world has ever received comes from the mind; the infinite library of the universe is in our own mind. – Swami Vivekananda. (1863 – 1902) Indian spiritual philosopher. The whole of science is nothing more than a refinement of everyday thinking. – Albert Einstein (1879 – 1955) German-Swiss-U.S. scientist. Science is a mechanism, a way of trying to improve your knowledge of na- ture. It’s a system for testing your thoughts against the universe, and seeing whether they match. – Isaac Asimov. (1920 – 1992) Russian-U.S. science-fiction author. VII Dedicated to the three KAs of my life: Kabilan, Rithika and Kavin. IX Abstract. Globalization has opened new frontiers for business enterprises and human com- munication. There is an information explosion that necessitates huge amounts of informa- tion to be speedily processed and acted upon. Information Systems aim to facilitate human decision-making by retrieving context-sensitive information, making implicit knowledge ex- plicit and to reuse the knowledge that has already been discovered. A possible answer to meet these goals is the use of Ontology.
    [Show full text]
  • An Ontology-Based Knowledge Management System for the Metal Industry
    An Ontology-based Knowledge Management System for the Metal Industry Sheng-Tun Li Huang-Chih Hsieh I-Wei Sun Department of Information Department of Information Metal Industries Research & Management, National Management, National Development Center Kaohsiung First University of Kaohsiung First University of 1001 Kaonan Highway, Nantz Science Technology Science Technology District, Kaohsiung, 811, Taiwan, 2 Juoyue Rd. Nantz District, 2 Juoyue Rd. Nantz District, R.O.C. Kaohsiung 811, Taiwan, R.O.C. Kaohsiung 811, Taiwan, R.O.C. +886-7-3513121 ext 2360 +886-7-6011000 ext 4111 +886-7-6011000 ext 4111 [email protected] [email protected] [email protected] failure of a procedure. These measurements and computations ABSTRACT such as measuring material size, computing machine stress, and Determining definite and consistent measurement and estimating manufacture frequency are usually formalized as computation of materials and operations is of great importance for mathematic models. In reality, each engineer has his (her) own the operation procedures in metal industry. The effectiveness and favorite model in use, and models could be revised or adjusted to efficiency of such decisions are greatly dependent on the domain be more practical and precise according to different requests of understanding and empirical experience of engineers. The engineers whereas adopting appropriate revise or adjustment is complexity and diversity of domain knowledge and terminology is based on the tacit knowledge and empirical experience of the major hurdle for a successful operation procedure. engineers or the related knowledge documents they have on hand. Fortunately, such hurdles can be overcome by the emerging However, with the diversity and complexity of conceptual ontology technology.
    [Show full text]
  • Introduction to Knowledge Engineering
    INTRODUCTION TO KNOWLEDGE ENGINEERING COURSE REVIEW Sistem Berbasis Pengetahuan Agenda 2 What is knowledge? Types of knowledge Knowledge engineering Knowledge engineers Philosophical Basis 3 Traditional questions that have been analyzed by philosophers, psychologists, and linguist: What is knowledge? What do people have inside their head when they know something? Is knowledge expressed in words? If so, how could one know things that are easier to do than to say, like tying a shoestring or hitting a baseball? If knowledge is not expressed in words, how can it be transmitted in language? How is knowledge related to the world? What are the relationships between the external world, knowledge in the head, and the language used to express knowledge about the world? Philosophical Basis 4 With the advent of computers, the questions addressed by the field of artificial intelligence (AI) are: Can knowledge be programmed in a digital computer? Can computers encode and decode that knowledge in ordinary language? Can they use it to interact with people and with other computer systems in a more flexible or helpful way? Information Processing Views of Knowledge 5 Hierarchical view: data information knowledge Information is the input or raw material of new knowledge Knowledge is authenticated/personalized information Reversed hierarchical view: knowledge information data Knowledge must exist before information can be formulated and before data can be collected Non-hierarchical view: data information Knowledge Knowledge is needed in converting data into information Knowledge is the accumulation of experiences vs. knowledge is created through conjectures and refutations. Alternative Perspectives on Knowledge 6 Knowledge can be defined as a justified belief that increases an entity’s capacity for effective action.
    [Show full text]
  • Rhetorical Structure Theory: Looking Back and Moving Ahead Maite Taboada and William C
    Discourse Studies http://dis.sagepub.com/ Rhetorical Structure Theory: looking back and moving ahead Maite Taboada and William C. Mann Discourse Studies 2006 8: 423 DOI: 10.1177/1461445606061881 The online version of this article can be found at: http://dis.sagepub.com/content/8/3/423 Published by: http://www.sagepublications.com Additional services and information for Discourse Studies can be found at: Email Alerts: http://dis.sagepub.com/cgi/alerts Subscriptions: http://dis.sagepub.com/subscriptions Reprints: http://www.sagepub.com/journalsReprints.nav Permissions: http://www.sagepub.com/journalsPermissions.nav Citations: http://dis.sagepub.com/content/8/3/423.refs.html Downloaded from dis.sagepub.com at SAGE Publications on March 23, 2011 ARTICLE 423 Rhetorical Structure Theory: looking back and moving ahead Discourse Studies Copyright © 2006 SAGE Publications. (London, Thousand Oaks, MAITE TABOADA CA and New Delhi) www.sagepublications.com SIMON FRASER UNIVERSITY, CANADA Vol 8(3): 423–459. WILLIAM C. MANN1 10.1177/1461445606061881 INDEPENDENT RESEARCHER ABSTRACT Rhetorical Structure Theory has enjoyed continuous attention since its origins in the 1980s. It has been applied, compared to other approaches, and also criticized in a number of areas in discourse analysis, theoretical linguistics, psycholinguistics, and computational linguistics. In this article, we review some of the discussions about the theory itself, especially addressing issues of the reliability of analyses and psychological validity, together with a discussion of the nature of text relations. We also propose areas for further research. A follow-up article (Taboada and Mann, forthcoming) will discuss applications of the theory in various fields. KEY WORDS: coherence, coherence relations, discourse signalling, discourse structure, intentions, Rhetorical Structure Theory (RST) 1.
    [Show full text]
  • Knowledge Engineering Research Topic Mining Based on Co-Word Analysis
    Knowledge Engineering Research Topic Mining Based on Co-word Analysis Xiumin Liu Zheng Liu National Science Library National Science Library Chinese Academy of Sciences Chinese Academy of Sciences Beijing, China Beijing, China [email protected] [email protected] Abstract—This paper collects research papers on knowledge engineering 2009-2018 from the internationally-authoritative II. DATA SOURCE citation database Web of Science and uses the co-word analysis This paper uses the international authoritative citation method to analyze these contents of literature. By statistical database Web of Science published by the American Institute analysis of keyword frequency, the paper compiles the co-word of Scientific Information (ISI) as the source of literature table of the high-frequency words, uses statistical analysis information. The paper intends to analysis the knowledge software to make hierarchical clustering, and summarizes hot engineering research topics, so that the search criteria are research topics in the knowledge engineering area. “topic or search keyword is knowledge engineering”, the Keywords-knowledge engineering; co-word analysis; topic search scope is 2009-2018, and the search time was February research; data process 12 2019 in the web of science database. The database has the added categories for each topic for more e. In the “knowledge engineering” subject, the “computer science interdisciplinary I. INTRODUCTION applications” or “computer science artificial intelligence” In 1977, Professor B.A. Feigenbaum, a computer scientist categories have been chosen for the limitation of the papers’ at Stanford University in the United States, presented a new content. A total of 1550 related articles were retrieved.
    [Show full text]