Cyril Cleverdon (9 September 1914 – 4 December 1997) was a British librarian and computer scientist who is best known for his work on the evaluation of information retrieval systems.
Cyril Cleverdon was born in Bristol, England. He worked at the Bristol Libraries from 1932 to 1938, and from 1938 to 1946 he was the librarian of the Engine Division of the Bristol Aeroplane Co. Ltd. In 1946 he was appointed librarian of the College of Aeronautics at Cranfield (later the Cranfield Institute of Technology), where he served until his retirement in 1979, the last two years as professor of Information Transfer Studies.
With the help of NSF funding, Cleverdon started a series of projects in 1957 that lasted for about 10 years in which he and his collegues set the stage for information retrieval research. In the Cranfield project, retrieval experiments were conducted on test databases in a controlled, laboratory-like setting. The aim of the research was to find ways to improve the retrieval effectiveness of information retrieval systems by developing better indexing languages and methods. The components of the experiments were: 1) a collection of documents, 2) a set of user requests or queries, and 3) a set of relevance judgments, that is a set of documents judged to be relevant to each query. Together, these components form an information retrieval test collection. The test collection serves as a golden standard for testing retrieval approaches, and the success of each approach is measured in terms of two measures: precision and recall. Test collections and evaluation measures based on precision and recall are driving forces behind research of search systems, today. Cleverdon's research approach forms a blue print for the successful Text Retrieval Conference series that started in 1992.
Cleverdon's Cranfield studies did not only introduce experimental research in computer science, the outcomes of the project also established the basis of the automatic indexing as done in today's search engines. Basically Cleverdon found that using single terms from the documents, as opposed manually assigned thesaurus terms, synonyms, etc. achieved the best retrieval performance. These results were very controversial at the time. In the Cranfield 2 Report, Cleverdon says:
This conclusion is so controversial and so unexpected that it is bound to throw considerable doubt on the methods which have been used (…) A complete recheck has failed to reveal any discrepancies (…) there is no other course except to attempt to explain the results which seem to offend against every canon on which we were trained as librarians.
Cyril Cleverdon also ran, for many years, the Cranfield conferences, which provided a major international forum for discussion of ideas and research in information retrieval. This function was taken over by the SIGIR conferences in the 1970's.
Cleverdon was awarded several times during his life. He received the Professional Award of the Special Libraries Association (1962), the Award of Merit of the American Society for Information Science (1971), and the Gerard Salton Award of the Special Interest Group on Information Retrieval of the Association for Computing Machinery (1991).
Written for Wikipedia.