I am a fourth year Ph.D. student in the Center for Applied Mathematics at Cornell University.
My research uses the tools of 'big data' to
better understand the structure of social systems,
social networks, and human decision making.
In doing so, my work examines large-scale computational problems at the intersection of
graph theory, probability theory, statistics, optimization, and algorithm design.
My advisor is Jon Kleinberg.
I currently co-ordinate the meetings of the Networks Journal Club at Cornell.
Since the summer of 2010 I have also held an affiliation with the Facebook Data Science team as a continuing graduate research intern.
I use Twitter, and you can find my infrequent tweets here. I recently started to keep a research blog to organize non-publication writing. Posts are expected to be very infrequent, but can be found here.
- Wired, April 2013: Exploring the Space of Human Interaction
- SmartPlanet, October 2012: Q&A: Why you have fewer friends than your friends on Facebook
- NY Times Opinionator, September 2012: Friends You Can Count On
- Nature, August 2012: Computational Social Science: Making the Links
- American Mathematical Society, July 2012: SIAM Annual Meeting 2012 Highlights
- Science Now, April 2012: How Facebook "Contagion" Spreads
- New Scientist, April 2012: Variety, Not Viral Spread, is Key to Facebook Growth
- The Economist, April 2012: Social Contagion: Conflicting Ideas
- The Economist, March 2012: The Sun Never Sets
- The Telegraph, March 2012: Facebook: British Empire Still Shapes Friendship Patterns
- NPR (on-air interview), November 2011: 4.74 Degrees of Separation
- TechCrunch, Novemeber 2011: 4.74 - Facebook Wins By Getting Us Closer Than Six Degrees
- NY Times, November 2011: Between You and Me? 4.74 Degrees
- (NEW) J Ugander, L Backstrom, J Kleinberg. Subgraph Frequencies: Mapping the Empirical and Extremal Geography of Large Graph Collections, Proc. 22nd Int'l World Wide Web Conf. (WWW), 2013.
(Companion webpage with R code.)
- (NEW) DM Romero, C Tan, and J Ugander. On the Interplay Between Social and Topical Structure, Proc. 7th AAAI Int'l Conf. on Weblogs and Social Media (ICWSM), 2013.
- J Ugander, L Backstrom. Balanced Label Propagation for Partitioning Massive Graphs, Proc. 6th ACM Int'l Conf. on Web Search and Data Mining (WSDM), 2013. (Best Student Paper Award)
- J Ugander, L Backstrom, C Marlow, J Kleinberg. Structural Diversity in Social Contagion, Proc. of the Nat'l Academy of Sciences (PNAS), 109(16) 5962-5966, 17 April 2012.
- J Ugander, B Karrer, L Backstrom, C Marlow, The Anatomy of the Facebook Social Graph. (pre-print)
- L Backstrom, P Boldi, M Rosa, J Ugander, S Vigna, Four Degrees of Separation, Proc. 4th ACM Int'l Conf. on Web Science (WebSci), 2012. (Best Paper Award)
- M Larsson, J Ugander, A Concave Regularization Technique for Sparse Mixture Models, Advances in Neural Information Processing Systems (NIPS) 24, 2011.
- J Ugander, Efficiency and Fragility in Loss Networks, May 2009. (Cambridge Part III Essay)
- J Ugander, RM Murray, Delay-Dependant Stability of Genetic Regulatory Networks. CSHL Meeting on Engineering Principles in Biological Systems, Cold Springs, NY, December 2008.
- J Ugander, Delay-dependent Stability of Genetic Regulatory Networks, M.Sc. Thesis, Department of Automatic Control, Lund University, July 2008.
- J Ugander, MJ Dunlop, RM Murray, Analysis of a Digital Clock for Molecular Computing. Proceedings of the 2007 American Control Conference (ACC), New York, July 2007. p. 1595-1599.
- J Ugander, B Karrer, L Backstrom, J Kleinberg. Clustered Graph Randomization: Network Exposure to Multiple Universes. (accepted, KDD 2013)
- J Nishimura, J Ugander. Restreaming Graph Partitioning: Simple Versatile Algorithms for Advanced Balancing. (accepted, KDD 2013)
A list of talks I've given, in addition to those implied by the conference proceedings publications above:
- WWW 2013 Workshop on Large Scale Network Analysis (LSNA), May 2013 (Keynote)
- Carnegie Mellon University, Statistical & Machine Learning Approaches to Network Experimentation Workshop, April 2013 (Invited)
- Cornell University, Computer Science Department Theory Colloquium, April 2013
- University of Washington Computer Science & Engineering Department Theory Seminar, February 2013
- Cornell University, Applied Mathematics Colloquium, October 2012
- NIPS 2012 Workshop on Algorithmic and Statistical Approaches for Large Social Networks, December 2012
- SIAM Annual Meeting, Massive Graphs: Big Compute meets Big Data Minisymposium, July 2012 (Invited)
- International Conference on Network Science (NetSci), June 2012
During 2008-2009 I studied applied mathematics and statistics at the University of Cambridge, UK, completing Part III of the Mathematical Tripos (CASM). For my Part III essay I was supervised by Frank Kelly. My essay proposed a model for systemic risk in interbank loan networks using mathematical techniques from models of telecommunication networks.
From 2004-2008, I studied Applied Mathematics at Lund University, Sweden, focusing my studies within the Department of Automatic Control. During the spring of 2008 I completed my M.Sc. thesis for Lund as a visiting student at the Department of Control and Dynamical Systems at Caltech, working under Richard Murray. This work studied delays in genetic regulatory networks, and developed a theoretical framework for engineering stability into gene regulation systems using delay.
I began my higher education at Deep Springs College, where I spent two years in the deserts of eastern California and my studies covered a broad range of liberal arts subjects. For more on Deep Springs, I recommend having a look at the wikipedia article.
I have previously done summer work on image segmentation and quantification algorithms in medical imaging, as a software developer for Medviso, a small Swedish start-up. In my younger years, during the summers of 1999-2000 (beginning when I was 14) I also worked as a system adminstrator for Spray Networks, Sweden's then-largest internet portal.
When not doing research, I clear my mind by rock-climbing, mountaineering, and skiing. I have been a member of the American Alpine Club since 2010. The above photo is from the top of Fairview Dome, Yosemite National Park, taken in August 2012.
I am a dual citizen of the United States and Sweden.
- Scholarfy: a simple bookmarklet I wrote to transfer search queries to Google Scholar.
Spectral theory for planar graphs:
Notes for a course guest lecture I gave, including the Spielman-Teng partitioning result. (9/29/2011)
- MATH7170 - Applied Dynamical Systems (S. Strogatz)
- CS6780 - Advanced Machine Learning (A. Saxena)
- CS6820 - Analysis of Algorithms (J. Kleinberg)
- CS6822 - Flows, Cuts, and Sparsifiers (R. Kleinberg)
- CS6840 - Algorithmic Game Theory (E. Tardos)
- CS6850 - The Structure of Information Networks (J. Kleinberg)
- ECON6090 - Microeconomic Theory (D. Easley)
- ECON6770 - Decision Theory II (A. Guerdjikova)
- ILRST7100 - Multivariate Analysis in Social Statistics (M. Wells)
- SOC6420 - Sociology of Diffusion (D. Strang)