John Ross Quinlan is a

computer science Computer science is the study of computation, automation, and information. Computer science spans theoretical disciplines (such as algorithms, theory of computation, information theory, and automation) to Applied science, practical discipli ...

researcher in data mining and

decision theory Decision theory (or the theory of choice; not to be confused with choice theory) is a branch of applied probability theory concerned with the theory of making decisions based on assigning probabilities to various factors and assigning numerical ...

. He has contributed extensively to the development of

decision tree A decision tree is a decision support tool that uses a tree-like model of decisions and their possible consequences, including chance event outcomes, resource costs, and utility. It is one way to display an algorithm that only contains condit ...

algorithms, including inventing the canonical C4.5 and

ID3 ID3 is a metadata container most often used in conjunction with the MP3 audio file format. It allows information such as the title, artist, album, track number, and other information about the file to be stored in the file itself. There are tw ...

algorithms. He also contributed to early

ILP ''ilp.'' () is the debut album by record producer and musician Kwes. It was released on 14 October 2013 on Warp Records. The release is a follow up to his second EP release '' Meantime''. The record's title ''ilp'' refers literally to the record ...

literature with First Order Inductive Learner (FOIL). He is currently running the compan
RuleQuest Research
which he founded in 1997.

Education

He received his BSc degree in Physics and Computing from the

University of Sydney The University of Sydney (USYD), also known as Sydney University, or informally Sydney Uni, is a public research university located in Sydney, Australia. Founded in 1850, it is the oldest university in Australia and is one of the country's si ...

in 1965 and his computer science doctorate at the

University of Washington The University of Washington (UW, simply Washington, or informally U-Dub) is a public research university in Seattle, Washington. Founded in 1861, Washington is one of the oldest universities on the West Coast; it was established in Seattle a ...

in 1968. He has held positions at the

University of New South Wales The University of New South Wales (UNSW), also known as UNSW Sydney, is a public research university based in Sydney, New South Wales, Australia. It is one of the founding members of Group of Eight, a coalition of Australian research-intensive ...

University of Technology Sydney The University of Technology Sydney (UTS) is a public research university located in Sydney, New South Wales, Australia. Although its origins are said to trace back to the 1830s, the university was founded in its current form in 1988. As of 2021 ...

, and

RAND Corporation The RAND Corporation (from the phrase "research and development") is an American nonprofit global policy think tank created in 1948 by Douglas Aircraft Company to offer research and analysis to the United States Armed Forces. It is financed ...

Artificial intelligence

Quinlan is a specialist in

artificial intelligence Artificial intelligence (AI) is intelligence—perceiving, synthesizing, and inferring information—demonstrated by machines, as opposed to intelligence displayed by animals and humans. Example tasks in which this is done include speech re ...

, particularly in the aspect involving

machine learning Machine learning (ML) is a field of inquiry devoted to understanding and building methods that 'learn', that is, methods that leverage data to improve performance on some set of tasks. It is seen as a part of artificial intelligence. Machine ...

and its application to data mining.Data Mining From an AI Perspective
/ref>

ID3

Ross Quinlan invented the Iterative Dichotomiser 3 (ID3) algorithm which is used to generate decision trees. ID3 follows the principle of

Occam's razor Occam's razor, Ockham's razor, or Ocham's razor ( la, novacula Occami), also known as the principle of parsimony or the law of parsimony ( la, lex parsimoniae), is the problem-solving principle that "entities should not be multiplied beyond neces ...

in attempting to create the smallest decision tree possible.

C4.5

He then expanded upon the principles used in ID3 to create C4.5. C4.5 improved: discrete and continuous attributes, missing attribute values, attributes with differing costs, pruning trees (replacing irrelevant branches with leaf nodes).

C5.0

C5.0, which Quinlan is commercially selling (single-threaded version is distributed under the terms of the

GNU General Public License The GNU General Public License (GNU GPL or simply GPL) is a series of widely used free software licenses that guarantee end users the Four Freedoms (Free software), four freedoms to run, study, share, and modify the software. The license was th ...

), is an improvement on C4.5. The advantages are speed (several orders of magnitude faster), memory efficiency, smaller decision trees, boosting (more accuracy), ability to weight different attributes, and winnowing (reducing noise).

Selected works

Books

* 1993. ''C4.5: Programs for Machine Learning''. Morgan Kaufmann Publishers. .

Articles

* Quinlan, J. R. (1982
Semi-autonomous acquisition of pattern-based knowledge
In Machine intelligence 10 (eds J. E. Hayes, D. Michie, and Y.-H. Pao). Ellis Norwood,Chichester. * Quinlan, J.R. (1985)
Decision trees and multi-valued attributes
In J.E. Hayes & D. Michie (Eds.), Machine intelligence 11. Oxford University Press. * Quinlan, J. R. (1986)
Induction of decision trees. Machine Learning, 1(1):81-106
* 2008. (with

Qiang Yang Qiang Yang () (born 1963) is the Chair Professor, Department Head of CSE, HKUST in Hong Kong and University New Bright Professor of Engineering and Chair Professor from 2015. He was the founding head of Noah's Ark Lab. He had taught at the Univer ...

, Philip S. Yu,

Zhou Zhihua Zhou Zhi-Hua (; born November 20, 1973) is a Professor of Computer Science at Nanjing University. He is the Standing Deputy Director othe National Key Laboratory for Novel Software Technology and Founding Director of thLAMDA Group His research int ...

, and David Hand et al). ''Top 10 algorithms in data mining''
Knowledge and Information Systems 14.1: 1-37
* Quinlan, J. R. (1990). Learning logical definitions from relations. Machine Learning, 5:239-266.

References

External links

Ross Quinlan's personal homepage
Machine learning researchers Living people Year of birth missing (living people) {{compu-bio-stub