Robert Tarjan Explained

Birth Name:Robert Endre Tarjan
Birth Date:April 30, 1948
Birth Place:Pomona, California, United States
Fields:Computer science
Workplaces:Princeton University
New York University
Stanford University
University of California, Berkeley
Cornell University
Microsoft Research
Intertrust Technologies
Hewlett-Packard
Compaq
NEC Research
Bell Labs
Alma Mater:California Institute of Technology (BS)
Stanford University (MS, PhD)
Thesis Title:An Efficient Planarity Algorithm
Thesis Url:https://dl.acm.org/citation.cfm?id=906252
Thesis Year:1972
Doctoral Advisor:Robert W. Floyd
Academic Advisors:Donald Knuth
Known For:Algorithms and data structures
Awards:Paris Kanellakis Award (1999)
Turing Award (1986)
Nevanlinna Prize (1982)
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Robert Endre Tarjan (born April 30, 1948) is an American computer scientist and mathematician. He is the discoverer of several graph theory algorithms, including his strongly connected components algorithm, and co-inventor of both splay trees and Fibonacci heaps. Tarjan is currently the James S. McDonnell Distinguished University Professor of Computer Science at Princeton University.

Personal life and education

He was born in Pomona, California. His father, George Tarjan (1912-1991), raised in Hungary,[1] was a child psychiatrist, specializing in mental retardation, and ran a state hospital.[2] Robert Tarjan's younger brother James became a chess grandmaster.[3] As a child, Robert Tarjan read a lot of science fiction, and wanted to be an astronomer. He became interested in mathematics after reading Martin Gardner's mathematical games column in Scientific American. He became seriously interested in math in the eighth grade, thanks to a "very stimulating" teacher.[4]

While he was in high school, Tarjan got a job, where he worked with IBM punch card collators. He first worked with real computers while studying astronomy at the Summer Science Program in 1964.[2]

Tarjan obtained a Bachelor's degree in mathematics from the California Institute of Technology in 1969. At Stanford University, he received his master's degree in computer science in 1971 and a Ph.D. in computer science (with a minor in mathematics) in 1972. At Stanford, he was supervised by Robert Floyd[5] and Donald Knuth, both highly prominent computer scientists, and his Ph.D. dissertation was An Efficient Planarity Algorithm. Tarjan selected computer science as his area of interest because he believed that computer science was a way of doing mathematics that could have a practical impact.[6]

Tarjan now lives in Princeton, NJ, and Silicon Valley. He is married to Nayla Rizk.[7] He has three daughters: Alice Tarjan, Sophie Zawacki, and Maxine Tarjan.[8]

Computer science career

Tarjan has been teaching at Princeton University since 1985.[6] He has also held academic positions at Cornell University (1972–73), University of California, Berkeley (1973–1975), Stanford University (1974–1980), and New York University (1981–1985). He has also been a fellow of the NEC Research Institute (1989–1997). In April 2013 he joined Microsoft Research Silicon Valley in addition to the position at Princeton. In October 2014 he rejoined Intertrust Technologies as chief scientist.

Tarjan has worked at AT&T Bell Labs (1980–1989), Intertrust Technologies (1997–2001, 2014–present), Compaq (2002) and Hewlett Packard (2006–2013).

Algorithms and data structures

Tarjan is known for his pioneering work on graph theory algorithms and data structures. Some of his well-known algorithms include Tarjan's off-line least common ancestors algorithm, Tarjan's strongly connected components algorithm, and Tarjan's bridge-finding algorithm, and he was one of five co-authors of the median of medians linear-time selection algorithm. The Hopcroft–Tarjan planarity testing algorithm was the first linear-time algorithm for planarity testing.[9]

Tarjan has also developed important data structures such as the Fibonacci heap (a heap data structure consisting of a forest of trees), and the splay tree (a self-adjusting binary search tree; co-invented by Tarjan and Daniel Sleator). Another significant contribution was the analysis of the disjoint-set data structure; he was the first to prove the optimal runtime involving the inverse Ackermann function.[10]

Awards

Tarjan received the Turing Award jointly with John Hopcroft in 1986. The citation for the award states[11] that it was:

Tarjan was also elected an ACM Fellow in 1994. The citation for this award states:[12]

Some of the other awards for Tarjan include:

Selected publications

Tarjan's papers have been collectively cited over 94,000 times.[19] Among the most cited are:

Patents

Tarjan holds at least 18 U.S. patents.[24] These include:

References

External links

Notes and References

  1. Web site: Jewish Recipients of the ACM A.M. Turing Award. jinfo.org.
  2. Book: Shasha , Dennis Elliott . Lazere, Cathy A. . Out of Their Minds: The Lives and Discoveries of 15 Great Computer Scientists . Copernicus/Springer . 1995 . 1998 . 978-0-387-97992-2 . 32240355 . Robert E. Tarjan: In Search of Good Structure . 102–119 . registration .
  3. Melvin. Shabsin. George Tarjan, M.D. one hundred twelfth president, 1983-1984. The American Journal of Psychiatry. 141. 8. 931-934. August 1984. 10.1176/ajp.141.8.931.
  4. Web site: Robert Tarjan: The Art of the Algorithm . Hewlett-Packard . 2010-09-05.
  5. Web site: Robert Endre Tarjan . Mathematics Genealogy Project . 2008-01-09.
  6. Web site: Robert Endre Tarjan: The art of the algorithm (interview) . September 2004 . Hewlett-Packard . 2008-01-09.
  7. Web site: Nayla Rizk and Robert Tarjan . July 2013 . The New York Times.
  8. Web site: Photos from Bob Tarjan's 60th Birthday Symposium . May 2008 . DIMACS.
  9. Book: Kocay , William . Kreher, Donald L . Graphs, algorithms, and optimization . limited . Chapman & Hall/CRC . Boca Raton . 2005 . 978-1-58488-396-8 . 56319851 . Planar Graphs . 312.
  10. Robert E. . Tarjan . Robert E. Tarjan . Jan . van Leeuwen . Jan van Leeuwen . Worst-case analysis of set union algorithms . . 31 . 2 . 245–281 . 1984 . 10.1145/62.2160. 5363073 . free .
  11. Web site: Robert E Tarjan — A.M. Turing Award Laureate. V.. King. ACM. 2014-01-19.
  12. Web site: Fellows Award — Robert E. Tarjan. September 25, 1998. ACM. 2005-11-18.
  13. Web site: Rolf Nevanlinna Prize Winners. https://web.archive.org/web/20081227210921/http://www.mathunion.org/general/prizes/nevanlinna/prize-winners/. 2008-12-27. International Mathematical Union. 2014-01-19.
  14. Web site: Robert Endre Tarjan. 2020-06-15. American Academy of Arts & Sciences. en.
  15. Web site: Robert Tarjan. 2020-06-15. www.nasonline.org.
  16. Web site: Dr. Robert E. Tarjan. 2020-06-15. NAE Website.
  17. Web site: APS Member History . 2022-04-19 . search.amphilsoc.org.
  18. Caltech Names Five Distinguished Alumni . 2010-03-15 . . 2010-08-26 . dead . https://web.archive.org/web/20101010023119/http://media.caltech.edu/press_releases/13332 . 2010-10-10 .
  19. Web site: Robert Tarjan Google Scholar Page . Google Scholar . 6 March 2023.
  20. Tarjan. Robert. 1972-06-01. Depth-First Search and Linear Graph Algorithms. SIAM Journal on Computing. 1. 2. 146–160. 10.1137/0201010. 16467262 . 0097-5397.
  21. Fredman. Michael L.. Tarjan. Robert Endre. 1987-07-01. Fibonacci heaps and their uses in improved network optimization algorithms. Journal of the ACM. 34. 3. 596–615. 10.1145/28869.28874. 7904683. 0004-5411. free.
  22. January 1983. Back Matter. Data Structures and Network Algorithms. 125–131. 10.1137/1.9781611970265.bm. 978-0-89871-187-5.
  23. Goldberg. Andrew V.. Tarjan. Robert E.. 1988-10-01. A new approach to the maximum-flow problem. Journal of the ACM. 35. 4. 921–940. 10.1145/48014.61051. 14492800. 0004-5411. free.
  24. Web site: Curriculum Vitae. Robert Endre. Tarjan. November 15, 2019. https://web.archive.org/web/20191123024149/https://www.cs.princeton.edu/~ret/Vita-Tarjan2019.pdf. 2019-11-23. 2019-11-23.
  25. Web site: United States Patent 4796003 — Data compaction. Bentley. Jon L.. Sleator. Daniel D. K.. Tarjan. Robert E.. January 3, 1989.
  26. Web site: United States Patent 7818272 — Method for discovery of clusters of objects in an arbitrary undirected graph using a difference between a fraction of internal connections and maximum fraction of connections by an outside object. Mishra. Nina. Schreiber. Robert Samuel. Tarjan. Robert E.. October 19, 2010.
  27. Web site: United States Patent 8220036 — Establishing a secure channel with a human user. Pinkas. Binyamin. Haber. Stuart A.. Tarjan. Robert E.. Sander. Tomas. July 10, 2012.