Knowledge retrieval
Encyclopedia
Knowledge Retrieval seeks to return information in a structured form, consistent with human cognitive processes
as opposed to simple lists of data items. It draws on a range of fields including epistemology (theory of knowledge), cognitive psychology
, cognitive neuroscience
, logic
and inference
, machine learning
and knowledge discovery
, linguistics
, and information technology
.
Both approaches require a user to read and analyze often long lists of data sets or documents in order to extract meaning.
The goal of knowledge retrieval systems is to reduce the burden of those processes by improved search and representation. This improvement is needed to leverage the increasing data volumes available on the Internet.
Knowledge retrieval (KR) focuses on the knowledge level. We need to examine how to extract, represent, and use the knowledge in data and information. Knowledge retrieval systems provide knowledge to users in a structured way. Compared to data retrieval and information retrieval, they use different inference
models, retrieval methods, result organization, etc. Table 1, extending van Rijsbergen’s comparison of the difference between data retrieval
and information retrieval, summarizes the main characteristics of data retrieval, information retrieval, and knowledge retrieval. The core of data retrieval and information retrieval is retrieval subsystems. Data retrieval gets results through Boolean match. Information retrieval uses partial match and best match. Knowledge retrieval is also based on partial match and best match.
From an inference perspective, data retrieval uses deductive inference
, and information retrieval uses inductive inference. Considering the limitations from the assumptions of different logics, traditional logic
systems (e.g., Horn
subset of first order logic
) cannot reasoning efficiently. Associative reasoning, analogical reasoning
and the idea of unifying reasoning and search may be effective methods of reasoning at the web scale.
From the retrieval perspective, knowledge retrieval systems focus on semantics and better organization of information. Data retrieval and information retrieval organize the data and documents by indexing, while knowledge retrieval organize information by indicating connections between elements in those documents.
perspective, a logic framework concentrating on fuzziness of knowledge queries has been proposed and investegated in detail. Markup language
s for knowledge reasoning and relevant strategies have been investigated, which may serve as possible logic reasoning foundations for text based knowledge retrieval.
From cognitive science
perspective, especially from cognitive psychology and cognitive neuroscience perspective, the neurobiological basis for knowledge retrieval in the human brain
has been investigated, and may serve as a cognitive model
for knowledge retrieval.
- Theory of Knowledge: knowledge acquisition, knowledge organization, knowledge representation
, knowledge validation, knowledge management.
- Cognitive Science: cognitive psychology, cognitive neuroscience, cognitive informatics, concept formation and learning, decision making, human–computer interaction
.
- Machine Learning and Knowledge Discovery: preprocessing, classification, clustering, prediction, postprocessing, statistical learning theory.
- Logic and Inference: propositional logic
, predicate logic, attribute logic, universal logic
, inductive inference
, deductive inference, associative reasoning, analogical reasoning, approximate reasoning.
- Information Technology: information theory
, information science
, information retrieval, database systems, knowledge-based systems
, rule-based systems, expert system
s, decision support system
s, intelligent agent
technology.
- Linguistics: computational linguistics
, natural language understanding, natural language processing
.
Topics listed under each entry serve as examples and do not form a complete list. And many related disciplines should be added as the field grows mature.
Cognition
In science, cognition refers to mental processes. These processes include attention, remembering, producing and understanding language, solving problems, and making decisions. Cognition is studied in various disciplines such as psychology, philosophy, linguistics, and computer science...
as opposed to simple lists of data items. It draws on a range of fields including epistemology (theory of knowledge), cognitive psychology
Cognitive psychology
Cognitive psychology is a subdiscipline of psychology exploring internal mental processes.It is the study of how people perceive, remember, think, speak, and solve problems.Cognitive psychology differs from previous psychological approaches in two key ways....
, cognitive neuroscience
Cognitive neuroscience
Cognitive neuroscience is an academic field concerned with the scientific study of biological substrates underlying cognition, with a specific focus on the neural substrates of mental processes. It addresses the questions of how psychological/cognitive functions are produced by the brain...
, logic
Logic
In philosophy, Logic is the formal systematic study of the principles of valid inference and correct reasoning. Logic is used in most intellectual activities, but is studied primarily in the disciplines of philosophy, mathematics, semantics, and computer science...
and inference
Inference
Inference is the act or process of deriving logical conclusions from premises known or assumed to be true. The conclusion drawn is also called an idiomatic. The laws of valid inference are studied in the field of logic.Human inference Inference is the act or process of deriving logical conclusions...
, machine learning
Machine learning
Machine learning, a branch of artificial intelligence, is a scientific discipline concerned with the design and development of algorithms that allow computers to evolve behaviors based on empirical data, such as from sensor data or databases...
and knowledge discovery
Knowledge discovery
Knowledge discovery is a concept of the field of computer science that describes the process of automatically searching large volumes of data for patterns that can be considered knowledge about the data . It is often described as deriving knowledge from the input data...
, linguistics
Linguistics
Linguistics is the scientific study of human language. Linguistics can be broadly broken into three categories or subfields of study: language form, language meaning, and language in context....
, and information technology
Information technology
Information technology is the acquisition, processing, storage and dissemination of vocal, pictorial, textual and numerical information by a microelectronics-based combination of computing and telecommunications...
.
Overview
In the field of retrieval systems, established approaches include:- Data Retrieval Systems (DRS), such as database management systemDatabase management systemA database management system is a software package with computer programs that control the creation, maintenance, and use of a database. It allows organizations to conveniently develop databases for various applications by database administrators and other specialists. A database is an integrated...
s, are well suitable for the storage and retrieval of structured data. - Information RetrievalInformation retrievalInformation retrieval is the area of study concerned with searching for documents, for information within documents, and for metadata about documents, as well as that of searching structured storage, relational databases, and the World Wide Web...
Systems (IRS), such as web search engineSearch engineA search engine is an information retrieval system designed to help find information stored on a computer system. The search results are usually presented in a list and are commonly called hits. Search engines help to minimize the time required to find information and the amount of information...
s, are very effective in finding the relevant documents or web pageWeb pageA web page or webpage is a document or information resource that is suitable for the World Wide Web and can be accessed through a web browser and displayed on a monitor or mobile device. This information is usually in HTML or XHTML format, and may provide navigation to other web pages via hypertext...
s.
Both approaches require a user to read and analyze often long lists of data sets or documents in order to extract meaning.
The goal of knowledge retrieval systems is to reduce the burden of those processes by improved search and representation. This improvement is needed to leverage the increasing data volumes available on the Internet.
Comparison of Data, Information and Knowledge Retrieval
Data Retrieval and Information Retrieval are earlier and more basic forms of information access.| Data Retrieval | Information Retrieval | Knowledge Retrieval | |
|---|---|---|---|
| Match | Boolean match | partial match, best match | partial match, best match |
| Inference | deductive inference | inductive inference | deductive inference, inductive inference, associative reasoning, analogical reasoning |
| Model | deterministic model | statistical and probabilistic model | semantic model, inference model |
| Query | artificial language | natural language | knowledge structure, natural language |
| Organization | table, index | table, index | knowledge unit, knowledge structure |
| Representation | number, rule | natural language, markup language | concept graph, predicate logic, production rule, frame, semantic network, ontology |
| Storage | database | document collections | knowledge base |
| Retrieved Results | data set | sections or documents | a set of knowledge unit |
Knowledge retrieval (KR) focuses on the knowledge level. We need to examine how to extract, represent, and use the knowledge in data and information. Knowledge retrieval systems provide knowledge to users in a structured way. Compared to data retrieval and information retrieval, they use different inference
Inference
Inference is the act or process of deriving logical conclusions from premises known or assumed to be true. The conclusion drawn is also called an idiomatic. The laws of valid inference are studied in the field of logic.Human inference Inference is the act or process of deriving logical conclusions...
models, retrieval methods, result organization, etc. Table 1, extending van Rijsbergen’s comparison of the difference between data retrieval
and information retrieval, summarizes the main characteristics of data retrieval, information retrieval, and knowledge retrieval. The core of data retrieval and information retrieval is retrieval subsystems. Data retrieval gets results through Boolean match. Information retrieval uses partial match and best match. Knowledge retrieval is also based on partial match and best match.
From an inference perspective, data retrieval uses deductive inference
Syllogism
A syllogism is a kind of logical argument in which one proposition is inferred from two or more others of a certain form...
, and information retrieval uses inductive inference. Considering the limitations from the assumptions of different logics, traditional logic
Term logic
In philosophy, term logic, also known as traditional logic or aristotelian logic, is a loose name for the way of doing logic that began with Aristotle and that was dominant until the advent of modern predicate logic in the late nineteenth century...
systems (e.g., Horn
Horn clause
In mathematical logic, a Horn clause is a clause with at most one positive literal. They are named after the logician Alfred Horn, who first pointed out the significance of such clauses in 1951...
subset of first order logic
First-order logic
First-order logic is a formal logical system used in mathematics, philosophy, linguistics, and computer science. It goes by many names, including: first-order predicate calculus, the lower predicate calculus, quantification theory, and predicate logic...
) cannot reasoning efficiently. Associative reasoning, analogical reasoning
Analogy
Analogy is a cognitive process of transferring information or meaning from a particular subject to another particular subject , and a linguistic expression corresponding to such a process...
and the idea of unifying reasoning and search may be effective methods of reasoning at the web scale.
From the retrieval perspective, knowledge retrieval systems focus on semantics and better organization of information. Data retrieval and information retrieval organize the data and documents by indexing, while knowledge retrieval organize information by indicating connections between elements in those documents.
Frameworks for Knowledge Retrieval systems
From computer scienceComputer science
Computer science or computing science is the study of the theoretical foundations of information and computation and of practical techniques for their implementation and application in computer systems...
perspective, a logic framework concentrating on fuzziness of knowledge queries has been proposed and investegated in detail. Markup language
Markup language
A markup language is a modern system for annotating a text in a way that is syntactically distinguishable from that text. The idea and terminology evolved from the "marking up" of manuscripts, i.e. the revision instructions by editors, traditionally written with a blue pencil on authors' manuscripts...
s for knowledge reasoning and relevant strategies have been investigated, which may serve as possible logic reasoning foundations for text based knowledge retrieval.
From cognitive science
Cognitive science
Cognitive science is the interdisciplinary scientific study of mind and its processes. It examines what cognition is, what it does and how it works. It includes research on how information is processed , represented, and transformed in behaviour, nervous system or machine...
perspective, especially from cognitive psychology and cognitive neuroscience perspective, the neurobiological basis for knowledge retrieval in the human brain
Human brain
The human brain has the same general structure as the brains of other mammals, but is over three times larger than the brain of a typical mammal with an equivalent body size. Estimates for the number of neurons in the human brain range from 80 to 120 billion...
has been investigated, and may serve as a cognitive model
Cognitive model
A cognitive model is an approximation to animal cognitive processes for the purposes of comprehension and prediction. Cognitive models can be developed within or without a cognitive architecture, though the two are not always easily distinguishable.In contrast to cognitive architectures, cognitive...
for knowledge retrieval.
Knowledge Retrieval related Disciplines
Knowledge retrieval can draw results from the following related theories and technologies:- Theory of Knowledge: knowledge acquisition, knowledge organization, knowledge representation
Knowledge representation
Knowledge representation is an area of artificial intelligence research aimed at representing knowledge in symbols to facilitate inferencing from those knowledge elements, creating new elements of knowledge...
, knowledge validation, knowledge management.
- Cognitive Science: cognitive psychology, cognitive neuroscience, cognitive informatics, concept formation and learning, decision making, human–computer interaction
Human–computer interaction
Human–computer Interaction is the study, planning, and design of the interaction between people and computers. It is often regarded as the intersection of computer science, behavioral sciences, design and several other fields of study...
.
- Machine Learning and Knowledge Discovery: preprocessing, classification, clustering, prediction, postprocessing, statistical learning theory.
- Logic and Inference: propositional logic
Propositional calculus
In mathematical logic, a propositional calculus or logic is a formal system in which formulas of a formal language may be interpreted as representing propositions. A system of inference rules and axioms allows certain formulas to be derived, called theorems; which may be interpreted as true...
, predicate logic, attribute logic, universal logic
Universal logic
Universal logic is the field of logic that is concerned with giving an account of what features are common to all logical structures. Universal logic aims to be to logic what universal algebra is to algebra; currently there is no universally accepted notion of logic...
, inductive inference
Inductive inference
Around 1960, Ray Solomonoff founded the theory of universal inductive inference, the theory of prediction based on observations; for example, predicting the next symbol based upon a given series of symbols...
, deductive inference, associative reasoning, analogical reasoning, approximate reasoning.
- Information Technology: information theory
Information theory
Information theory is a branch of applied mathematics and electrical engineering involving the quantification of information. Information theory was developed by Claude E. Shannon to find fundamental limits on signal processing operations such as compressing data and on reliably storing and...
, information science
Information science
-Introduction:Information science is an interdisciplinary science primarily concerned with the analysis, collection, classification, manipulation, storage, retrieval and dissemination of information...
, information retrieval, database systems, knowledge-based systems
Knowledge-based systems
Knowledge based systems are artificial intelligent tools working in a narrow domain to provide intelligent decisions with justification. Knowledge is acquired and represented using various knowledge representation techniques rules, frames and scripts...
, rule-based systems, expert system
Expert system
In artificial intelligence, an expert system is a computer system that emulates the decision-making ability of a human expert. Expert systems are designed to solve complex problems by reasoning about knowledge, like an expert, and not by following the procedure of a developer as is the case in...
s, decision support system
Decision support system
A decision support system is a computer-based information system that supports business or organizational decision-making activities. DSSs serve the management, operations, and planning levels of an organization and help to make decisions, which may be rapidly changing and not easily specified in...
s, intelligent agent
Intelligent agent
In artificial intelligence, an intelligent agent is an autonomous entity which observes through sensors and acts upon an environment using actuators and directs its activity towards achieving goals . Intelligent agents may also learn or use knowledge to achieve their goals...
technology.
- Linguistics: computational linguistics
Computational linguistics
Computational linguistics is an interdisciplinary field dealing with the statistical or rule-based modeling of natural language from a computational perspective....
, natural language understanding, natural language processing
Natural language processing
Natural language processing is a field of computer science and linguistics concerned with the interactions between computers and human languages; it began as a branch of artificial intelligence....
.
Topics listed under each entry serve as examples and do not form a complete list. And many related disciplines should be added as the field grows mature.