Amy N. Langville, Professor and Mathematical Consultant

Amy N. Langville

Professor
Mathematics Department
Operations Research Analyst
College of Charleston
175 Calhoun Street
4 Greenway #201
Charleston, SC 29401
P: 843-953-5730, F: 843-953-1410
langvillea@cofc.edu

Books

History

Research Interests

Mathematical Consulting

Publications

Conferences and Talks

Teaching

Curriculum Vita

Operations Research

Books

The Deconstruct Calculus Project
Who's #1: The Science of Rating and Ranking --2012, Princeton University Press, with Carl Meyer.
Google's PageRank and Beyond: The Science of Search Engine Rankings. Amy N. Langville and Carl D. Meyer. Princeton University Press, June 2006.

Older Links

College of Charleston Distinguished Teacher-Scholar Award.
College of Charleston EXCEL Faculty of the Year Award.
Sudoku Puzzles: solved by an Integer Programming Model, with Matlab code
Web Graph Datasets and Code for the PageRank problem
Device Dissection Laboratory ---A NSF-funded virtual laboratory containing online modules designed to let mathematics students dissect mathematical concepts and algorithms. One module teaches students how search engines work; another how numerical algorithms for differential equations work.
Markov Anniversary Meeting 2006---recent conference on Markov chains, including the life and history of A.A. Markov, famous applications, past and present of his chains, and the theory and numerical solution of Markov chains; College of Charleston, June 12-14, 2006.
Carl Meyer's 60th birthday celebration held in Raleigh, NC on Thursday, May 15, 2003.
An annotated bibliography of papers about Markov chains and information retrieval, ps pdf
Classic Runabout Project---A project with my brother Chad. A dual cockpit outboard runabout in the classic wooden boat style, named Langville Bros. after my grandfather and great uncle.

History

2005-present College of Charleston. I started my academic career in the Mathematics department, met my husband, and took up surfing at Folly Beach.
2002-2005 N.C. State University. I enjoyed a postdoctoral position in the Mathematics department, studying the mathematics behind search engines like Google.
1997-2002 N.C. State University. I came to Raleigh, NC for a Ph.D. in Operations Research. I filled my time taking outdoor recreation P.E. classes, playing some volleyball, more basketball and learning about Markov chains.
1993-1997 Mount Saint Mary's College. I hiked in the mountains near Emmitsburg, MD, played lots more basketball, some volleyball, visited the grotto and majored in Mathematics.
1989-1993 Archbishop Spalding High School . I grew up in Arnold, MD, 3 miles north of Annapolis. I spent most of my time playing basketball and volleyball and boating with my grandfather.

Research Interests

Ranking and Rankability with Dr. Paul Anderson and Kathryn Pedings-Behling
Linear programs, integer programs, and optimization for ranking and clustering, with Dr. Yoshitsugu Yamamoto
Search engines, Markov chains, information retrieval, and text analysis with Dr. Carl D. Meyer
The Nonnegative Matrix Factorization, information retrieval, and text analysis, with The SAS Institute
Markov chains and stochastic automata networks, with Dr. William J. Stewart

Mathematical Consulting, Scientific Expert, Patent Infringement Cases, and Advisory Boards

The Boeing Corporation, Markov chains and linear systems, 2004-2005
The SAS Institute, text analysis, document clustering, and the nonnegative matrix factorization, 2005-2007
Semandex, Inc., text analysis and network analysis, 2007-present
Piffany, Search Engine for Kids, 2008-2010
Fortune Interactive, Search Engine Optimization, 2007-2008
Your Music On, 2009-2010
College Football Performance Awards, ranking athletes for awards, 2009-2011
SKV Law Firm, patent infringement case regarding link analysis algorithms used by search engines such as Google, Yahoo, Bing, and AOL, 2007-2012
Prediculous, recommendation system, 2010-2012
DPEH Law Firm, patent infringement case regarding link analysis algorithms used by social networks such as Facebook, Twitter, and LinkedIn 2012-2014
xCures, ranking cancer treatments for patients with the cancer research company xCures, 2021-2022
Irell & Manella, patent infringement case on web search, 2021-present

Publications

Michael W. Berry, Timothy P. Chartier, Kevin Huston, and Amy N. Langville. Identifying Influential Edges in a Directed Network: big events, upset, and non-transitivity. Journal of Complex Networks. under review.
Amy N. Langville and Carl D. Meyer. Who's #1: The Science of Rating and Ranking. Princeton University Press, 2012.
Amy N. Langville and Carl D. Meyer. Do the Math: no ranking system is No. 1: why rankings are flawed. Scientific American. June 26, 2012, p. 1-3.
Timothy P. Chartier, Erich Kreutzer, Amy N. Langville, Daniel A. Martin and Kathryn Pedings. Accounting for Ties when Ranking Items. Journal of Quantitative Analysis in Sports. under review.
Timothy P. Chartier, Erich Kreutzer, Amy N. Langville, and Kathryn Pedings. Survival of the Fittest: Evolutionary Optimization and Ranking. LOCI. to appear. html
Amy N. Langville, Kathryn Pedings, and Yoshitsugu Yamamoto. A Minimum Violations Ranking Method. Optimization and Engineering. 2011, p. 1-22.
Timothy P. Chartier, Erich Kreutzer, Amy N. Langville, and Kathryn Pedings. Sensitivity and Stability of Ranking Methods. SIAM Journal on Scientific Computing, 2011, 33(3):1077-1102. SIAM nugget. IEEE podcast.
Timothy P. Chartier, Erich Kreutzer, Amy N. Langville, and Kathryn Pedings. Sports Ranking with nonuniform weighting. Journal of Quantitative Analysis in Sports, 2011, 7(3), Article 6.
Timothy P. Chartier, Erich Kreutzer, Amy N. Langville, Kathryn Pedings, and Yoshitsugu Yamamoto. Mininum Violations Sports Ranking using Evolutionary Optimization and Binary Integer Linear Program Approaches. Proceedings of the Tenth Australian Conference on Mathematics and Computers in Sports. Mathsport, 2010:13-20.
Timothy P. Chartier, Amy N. Langville and Peter Simov. March Madness to Movies. Math Horizons, April 2010: 16-19.
E. Aghapour, T. Chartier, B. Kovacevich, A. Langville, K. Pedings. Google's PageRank: The Mathematics of Google. SIAM Why do Math? SIAM, 2010. html and video
Timothy P. Chartier, Erich Kreutzer, Amy N. Langville, and Kathryn Pedings. Bracketology: How can math help? Joint Policy Board of Mathematics, Mathematics Awareness Month 2010.
Timothy P. Chartier, Erich Kreutzer, Amy N. Langville, and Kathryn Pedings. Google-opoly. LOCI, 2010.
Anjela Y. Govan, Amy N. Langville and Carl D. Meyer. Offense-defense approach to ranking team sports. Journal of Quantitative Analysis in Sports. 2009, 5(1), Article 4.
Amy N. Langville, Michael W. Berry, Murray Browne, V. Paul Pauca, and Robert J. Plemmons. Algorithms and Applications for Approximate Nonnegative Matrix Factorization. Computational Statistics and Data Analysis. 52(1):155-173, 2007. html. pdf
Brett W. Bader, Michael W. Berry, and Amy N. Langville. Nonnegative Matrix and Tensor Factorization for Discussion Tracking, Text Mining: Theory, Applications, and Visualization, Chapman & Hall, 2009.
Amy N. Langville and Michael W. Berry. Nonnegative Matrix Factorization for Anomaly and Trend Detection. Next Generation of Data Mining, H. Kargupta, J. Han, P. Yu, R. Motwani, and V. Kumar eds., CRC Press, p. 335-352, 2008.
Andrew Bartlett, Timothy Chartier, Amy N. Langville, and Timothy Rankin. An Integer Programming Model for the Sudoku Problem. Journal of Online Mathematics and its Applications. MAA, (8):1-14, 2008.
Amy N. Langville and Carl D. Meyer. Google's PageRank and Beyond: The Science of Search Engine Rankings. Princeton University Press, June 2006.
Amy N. Langville, Carl D. Meyer, Russell Albright, James Cox, and David Duling. Initializations, Algorithms, and Convergence for the Nonnegative Matrix Factorization. Preprint.
Amy N. Langville and Carl D. Meyer. Information Retrieval and Web Search. The Handbook of Linear Algebra. CRC Press, 2006.
Amy N. Langville and William J. Stewart. Proceedings of the Markov Anniversary Meeting. Boson Press, 2006.
Amy N. Langville and Carl D. Meyer. Updating Markov Chains. Proceedings of the Markov Anniversary Meeting. Boson Press, 2006.
Philipp von Hilgers and Amy N. Langville. The Five Greatest Applications of Markov Chains. Proceedings of the Markov Anniversary Meeting. Boson Press, 2006.
Andre Berger, Nader Razouk, Greg Angelides, Andy Bartlett, Amy N. Langville, Zhilin Li, Craig Lipkin, Nsoki Mavinga, Elizabeth Perez, Eamonn Tweedy, Erik Wheeler. Locally Constrained Shortest Paths and an Application in Mission Planning. Proceedings of the Forty-Fourth ACM Southeast Conference. ACM, March 2006.
Andre Berger, Nader Razouk, Greg Angelides, Andy Bartlett, Amy N. Langville, Zhilin Li, Craig Lipkin, Nsoki Mavinga, Elizabeth Perez, Eamonn Tweedy, Erik Wheeler. Optimal Mission Planning. Proceedings of the Eleventh Industrial Mathematical and Statistical Modeling Workshop. CRSC-TR05-46 Technical Report, 2005, p. 1-17.
Amy N. Langville and Carl D. Meyer. Updating the Stationary Vector of an Irreducible Markov Chain with an Eye on Google's PageRank. SIAM Journal on Matrix Analysis, 27(4): 968-987, SIAM News article on this work
Amy N. Langville and Carl D. Meyer. Deeper Inside PageRank. Internet Mathematics, Vol. 1(3):335-380, 2005.
Amy N. Langville and Carl D. Meyer. A Survey of Eigenvector Methods of Web Information Retrieval. The SIAM Review, 47(1):135-161, 2005.
Amy N. Langville and Carl D. Meyer. The Use of Linear Algebra by Web Search Engines. IMAGE Newsletter, 33:2-6, Dec. 2004.
Amy N. Langville and Carl D. Meyer. A Reordering for the PageRank problem. SIAM Journal on Scientific Computing.
Amy N. Langville and Carl D. Meyer. Updating PageRank with Iterative Aggregation. Proceedings of the Thirteenth World Wide Web Conference. New York: ACM Press, 392-393, 2004.
Amy N. Langville and William J. Stewart, eds. Proceedings of the Fourth International Conference on the Numerical Solution of Markov Chains. September 2003. University of Illinois at Urbana-Champaign.
Gely P. Basharin, Amy N. Langville, and Valeriy A. Naumov. The Life and Work of A. A. Markov. Linear Algebra and its Applications. Vol. 386:3-26, 2004.
Amy N. Langville. The Linear Algebra behind Search Engines. Journal of Online Mathematics and its Applications (JOMA), December 2005,
Amy N. Langville and William J. Stewart. A Kronecker Product Approximate Preconditioner for SANs. Numerical Linear Algebra with Applications, 11(8):723-752, 2004.
Amy N. Langville. The Kronecker Product and Stochastic Automata Networks Journal of Computational and Applied Mathematics, 167(2):429-447, 2004.
Amy N. Langville and William J. Stewart. Testing the nearest Kronecker product preconditioner on MCs and SANs. INFORMS Journal on Computing, 16(3):300-315, 2004.
Amy N. Langville. Preconditioning for Stochastic Automata Networks. Ph.D. dissertation, N.C. State University, Raleigh, NC. March 2002.
Amy N. Langville. Catastrophic Cancellation on the High Seas. Pi Mu Epsilon. 11(4):205-208, 2001.
Norm Curet and Amy N. Langville. Applying Mathematical Programming Techniques to the Network Diversion Problem. NSA Unclassified Internal Report. R55-TECH-052-98. Sept. 1998.

Conferences and Talks

MAA State Dinner Keynote Speaker, Coastal Carolina University. Oct. 29, 2013. Random Search, Ordered Results.
Kennesaw State University, Infinite Horizons Speaker. Sept. 13, 2013. Random Search, Ordered Results.
Kennesaw State University, Infinite Horizons Speaker. Sept. 13, 2013. My Life as a Mathematical Consultant.
Carolina Sports Analytics Meeting, Invited Panelist. Furman University, Apr. 13, 2013.
National Museum of Mathematics, New York, NY, Math Encounters Speaker. Jan. 2, 2013. Random Search, Ordered Results: how search engines use mathematics to organize the web.
NIPS Social Choice Workshop, Keynote Speaker. Dec. 8, 2012. Ranking by Optimization.
Mt. Olive College, NC, Martin Lecture, Invited Keynote Speaker. Presentation Mar. 4, 2011. Google-opoly.
College of Charleston, SC, Math Meet, Invited Keynote Speaker. Feb. 20, 2010. Google-opoly.
AIM Mathematics of Ranking Conference, Stanford, CA, Aug. 18, 2010. PageRank from 1998 to Now.
SIAM Southeastern Sectional Meeting, Raleigh, NC, Mar. 21, 2010. Ranking by Optimization Methods.
MAA Southeastern State Dinner, Charleston, SC, Mar. 30, 2009. Mathematics Everywhere: from Google to Sudoku to NCAA to Netflix.
Tsukuba University, PhilOpt Seminar. Tokyo, Japan, Jan. 30, 2009. The Science of Rating Items: from webpages to teams to movies.
SEAMS Cha Cha Days. Chapel Hill, NC, Nov. 2, 2008. Rank and Rating Aggregation.
Hamilton Institute, Maynooth, Ireland, Invited Lecturer. Aug. 8, 2008. Applications of Nonnegative Matrices: Ranking and Clustering.
Hamilton Institute, Maynooth, Ireland, Workshop on Nonnegative Matrices. Aug. 8, 2008. Rank and Rating Aggregation.
N.C. State University, Graduation Speaker, Physical and Mathematical Sciences. May 10, 2008. 5 Lessons for Graduates.
Mathematics Department Colloquium. Southern Methodist University. Dallas, TX. Nov. 14, 2007. Google's PageRank and Beyond: The Science of Search Engine Rankings.
ACM Colloquium. The College of Charleston, SC. Oct. 23, 2007. Google's PageRank and Beyond: The Science of Search Engine Rankings.
Mathematics and Computer Science Colloquium. The Citadel, Charleston, SC. Oct. 16, 2007. Google's PageRank and Beyond: The Science of Search Engine Rankings.
Workshop on Numerical Linear Algebra, the Internet and its Applications. Monopoli, Italy. Sept. 11, 2007. Clustering with the SVD.
14th Conference of the International Linear Algebra Society. Shanghai, China. July 16, 2007. Google's PageRank and Beyond: The Science of Search Engine Rankings.
AMS Southeastern Sectional Meeting. Davidson College. Davidson, NC. March 3-4, 2007. Symposium Organizer for "Applications in Numerical Linear Algebra."
Workshop on the Nonnegative Matrix Factorization. Raleigh, NC. Feb. 23, 2007. The Nonnegative Matrix Factorization: a tutorial.
Web Information Retrieval and Link Analysis Conference. Dagstuhl, Germany. Feb. 14, 2007. Clustering with the SVD and NMF.
Univ. of Illinois at Urbana-Champaign, Webmasters Forum. Jan. 25, 2007. Google's PageRank and Beyond: The Science of Search Rankings.
Univ. of Illinois at Urbana-Champaign, Women in Computer Science Seminar. Jan. 25, 2007. An Introduction to the Use of Link Analysis by Web Search Engines.
Radio Broadcast on AirTalk (program on So. Calif.'s public radio 89.3 KPCC-FM) Nov. 28, 2006. The Science of Search Engine Rankings. streaming mp3 mp3
AMS Talk on Capitol Hill. Washington, DC, Nov. 16, 2006. The Necessity of Mathematics: From Google to Counterterrorism to Sudoku.
Conference on Mathematical Models in Counterterrorism. Capitol Hill, DC, Sept. 25-26, 2006.
Algorithms for Modern Massive Datasets. Stanford, CA, June 21-24, 2006.
A.A. Markov Anniversary Meeting. Charleston, SC, June 12-14, 2006. The Five Greatest Applications of Markov Chains.
The Boeing Company. Bellevue, WA, May 18, 2006. The Nonnegative Matrix Factorization in Data Mining.
Davidson College. Charlotte, NC, February 16, 2006. Mathematics Department Seminar. An Introduction to the Use of Link Analysis by Web Search Engines.
INFORMS Annual Meeting. San Francisco, CA, November 14, 2005. The Nonnegative Matrix Factorization in Data Mining.
Yahoo! Research. San Francisco, CA, October 18, 2005. The Nonnegative Matrix Factorization in Data Mining.
SIAM Annual Meeting. New Orleans, LA, July 11-15, 2005. Invited Symposium Organizer for "Eigenvector Methods in Information Retrieval." Introduction to Eigenvector Methods in Information Retrieval.
Department of Energy Computational Science Graduate Fellowship Annual Fellows' Conference. Washington, DC, June 21-23, 2005. Invited Speaker. Information Retrieval and Computing: The Big Picture.
University of Delaware, SIAM Student Chapter Seminar. Newark, DE, May 5, 2005. An Introduction to the Use of Link Analysis by Web Search Engines.
SIAM Southeastern Section Annual Meeting. Charleston, SC, March 25-26, 2005. Text Mining using the Nonnegative Matrix Factorization.
MAA Southeastern Section 84th Annual Meeting. Raleigh, NC, March 11-12, 2005. Information Retrieval and Web Search. Part 1 pdf Part 2 pdf
SIAM Computational Science and Engineering Conference. Orlando, FL, February 11-15, 2005. Updating the Stationary Vector of an Irreducible Markov Chain.
Columbia University, Inaugural SIAM Student Chapter Seminar. New York, NY, November 23, 2004. An Introduction to the Use of Link Analysis by Web Search Engines.
Southeastern Atlantic Mathematics Sciences Workshop. Charleston, SC, September 17-19, 2004. An Introduction to the Use of Link Analysis by Web Search Engines.
SIAM Annual Meeting. Portland, OR, July 12-16, 2004. Mini-symposium Organizer for "Markov Chains and PageRank." Presentation: An Introduction to the Use of Link Analysis by Google.
The Mathematics of Web Search and Meta-Search. Bertinoro, Italy, June 19-26, 2004. Presentation: Updating and Reordering for the PageRank Problem
World Wide Web Conference. New York, NY, May 19-21, 2004. Poster Presentation: Updating PageRank with Iterative Aggregation
Mt. St. Mary's College, Mathematics and Computer Science Seminar. Emmitsburg, MD. April 19, 2004. An Introduction to the Use of Link Analysis by Web Search Engines, pdf
College of Charleston, Mathematics Seminar. Charleston, SC. February 27, 2004. Solution Methods for the PageRank Problem
Emory University, Computational Mathematics Seminar. Atlanta, GA. January 30, 2004. Updating PageRank
Stanford University, Scientific Computing and Computational Mathematics Seminar. Palo Alto, CA. November 17, 2003. Updating PageRank, pdf
Fourth International Conference on the "Numerical Solution of Markov Chains". University of Illinois at Urbana-Champaign. September 3-5, 2003. Co-Chair. Keynote Address: The Life and Work of A. A. Markov
Fourth International Conference on the "Numerical Solution of Markov Chains". University of Illinois at Urbana-Champaign. September 3-5, 2003. Co-Chair. Work-in-Progress Presentation: Updating the Stationary Solution of an Irreducible Markov Chain
SIAM Conference on Applied Linear Algebra. Williamsburg, VA, July 15-19, 2003. Mini-symposium Organizer for "Search Engines, Markov Chains and Clustering." Presentation: An Introduction to Markov-based Information Retrieval Systems
Matrix Analysis and Applied Linear Algebra: A celebration honoring Carl D. Meyer on the occasion of his 60th birthday. Co-Chair. N.C. State University, Raleigh, NC, May 15, 2003.
SIAM International Conference on Data Mining with Text Mining Workshop. San Francisco, CA, May 1-3, 2003.
Talk for The Boeing Company. Seattle, WA. January 23, 2003. Markov Chains, Information Retrieval and the Updating Problem.
College of Charleston. Charleston, SC. November 1, 2002. Markov Chains, Information Retrieval and the Updating Problem.
College of Charleston. Charleston, SC. April 11, 2002. MCs, SANs and Search Engines. pdf
SIAM International Conference on Data Mining with Text Mining Workshop. Arlington, VA, April 11-13, 2002.
Preconditioning Techniques for Large Sparse Matrix Problems in Industrial Applications, Tahoe City, CA, April 29-May 1, 2001. Presentation: Preconditioning for SANs.