Calvin Northrup Mooers

Calvin Mooers (1919-1994) was an American information retrieval specialist.

Life

Calvin Northrup Mooers was born on October 24, 1919 in Minneapolis. He graduated BA summa cum laude at the University of Minnesota in 1941 and joined the Naval Ordnance Laboratory as a physicist. At the end of the war he became part of the Lab's newly created Computer Division under John Vincent Atanasoff. Mooers left in 1946 for MIT where he completed a Master degree with a thesis on Application of random codes to gathering of statistical information. At MIT he met James Perry and became interested in information retrieval. In 1947 Mooers founded the proprietary Zator Company, and began marketing custom-designed mechanical retrieval systems using edge-notched cards. Raymond J. Solomonoff, interested in artificial intelligence, joined Mooers. Mooers created the Rockford Research Institute, a nonprofit corporation, in the early 1960s to facilitate his and Solomonoff’s grant-funded research. He died on December 1, 1994.

Contributions

• Mooers coined the terms "information retrieval" in 1950 and "descriptors."
• He promulgated "Mooers' Law": "An information system will tend not to be used whenever it is more painful and troublesome for a customer to have information than for him not to have it." (Bulletin of ASIS 22, no 1 (Oct/Nov 1996): 22-23).

TRAC programming language

In 1959, Mooers began to develop the Text Reckoning and Compiling (TRAC) language. Doug Engelbart, famous for “point and click,” used the his mechanical mouse in his famous 1968 demonstration to point and the "active function" of Mooers' TRAC language to click.

"In summary, Engelbart may be remembered as the “point” man, and Mooers as the “click” man. The point facility that Engelbart gave Mooers was just what he needed for the click facility. Mooers had described the function, but a more effective execution of the function awaited the mouse hardware." (Bemer 2004).

Zatocoding

Although Mooers was involved in the early design of digital computers, he made his name through his development of Zatocoding for edge-notched cards. Before the 1980s individuals made heavy use of cards which had a row of small round holes along the edges of a card. Cutting away card between the hole and the edge left a notch instead of a hole. In a simple case each card might represent a book and each hole could represent a possible feature (attribute), such as a topic of the book. If a card represented a book, notching the hole for "history" would code it as a history book. Notching a hole representing "France" would code it as a book about France. Notching both the "history" and the "France" holes would identify a book about the history of France. Cards with desired notches were immediately identifiable by inserting needle (or similar) through the hole(s) (code(s)) of interest and lifting. Intact (unnotched) cards would be lifted; notched cards would remain unlifted.

In a simple system in which each hole had only a single meaning, the number of usable codes (attributes) was limited because the number of codes could not exceed the number of holes. Mooers explored the potential of using combinations of two or more holes to represent a single code. This meant, in theory, that there could also be as many additional different codes as there were unique combinations of two or more holes. In this case a given hole might be part of multiple combinations but each combination of holes should represent only a single code. In the mechanical system that the Zator company marketed each card had just 40 holes along the bottom edge. By using combinations of holes up to 10,000 different codes could be uniquely encoded -- and any cards wrongly retrieved ("false drops") should be obvious errors.

Mooers explored the effects of assigning combinations of holes to codes at random. He concluded that conventional single hole coding was superior for codes having little variety and high frequency, but that Zatocoding had a complementary advantage for codes with large variety and low frequency. This technique can also be applied to encoding positions on punch cards. It is also known as superimposed coding. It is a form of what in computing is called a hash code. (See Further reading below).  

Publications

• "Atanasoff at the Naval Ordnance Laboratory." Annals of the History of Computing 15:2 (1993), 54-55.
• "Calvin Mooers, the NOL computer project, and John Vincent Atanasoff." IEEE Annals of the History of Computing 23, issue 2 (April-June 2001): [?52-?67]. With introduction by Michael R. Williams on pp 50-51.
• "TRAC, a Procedure-Describing Language for the Reactive Typewriter." Communications of the Association for Computing Machinery, 9:3 (March 1966), 215-219.
• Putting Probability to Work in Coding Punched Cards: Zatocoding. (Zator Technical Bulletin No. 10), 1947. Reprinted as Zator Technical Bulletin No. 30 (1950).
• The Zator - A Proposal: A Machine for Complete Documentation, 1947. Reprinted with preface as Zator Technical Bulletin No. 65 (1951).
• "Zatocoding applied to mechanical organization of knowledge." American documentation 2, issue 1 (Jan 1951): 20-32.
• "'Mooers' Law or Why some retrieval systems are used and others are not." Bulletin of the American Society for Information Science 22, no 1 (Oct/Nov 1996): 22-23. [1]
• Calvin N. and Charlotte D. Mooers oral history interview, 22 June 1993, OH 254, [2]

Awards

• American Society for Information Science. Award of Merit, 1978.

Further reading

• Babbage Institute Finding list [3]
• Weiss, E. "Obituary for Calvin Mooers." IEEE Annals of the History of Computing 46, issue 3 (Fall-1995): 79-81.

TRAC

• "TRAC (programming language)." Wikipedia [4]
• Bemer, Bob. "Calvin Mooers - How he came to be known as the "click" man." IEEE Annals of the History of Computing 26, Issue 1 (Jan-Mar 2004): 66-67.
• TRAC Foundation website, archived. [5]

Zatocoding:

• "Superimposed code." Wikipedia [6]
• Ceruzzi, Paul E. "Calvin Mooers, Zatocoding, and Early Research on Information Retrieval." In: Exploring the Early Digital, ed. T. Haigh. Cham : Springer International Publishing, 2019, pp.69-86.

Papers

• University of Minnesota, Babbage Institute, Minneapolis, MN. Calvin N. Mooers papers CBI 81 55455. ca. 1930-1994. Finding aid [7]