Todd Mytkowicz Graduate Student in Computer Science B.S. Computer Science, Syracuse University '01 email: mytkowit @ colorado.edu office:   ECCR B121 CV:   resume.pdf
Dynamical Systems & Performance Analysis

Computer Dynamics Lab

Research

	Physics of Multicore Computation Collaborators Amer Diwan: My advisor here at CU Peter Sweeney : IBM Research Matthias Hauswirth : University of Lugano, CH Whether we like it or not, multicore computation is here to stay. Along with multicore comes the increased complexity of parallel computation. Our approach to this problem is a pragmatic one; we are building tools to accommodate the increased complexity in understanding where performance bottlenecks arise in multicore computing.
	Chaos in computer systems Collaborators Amer Diwan: My advisor here at CU Elizabeth Bradley : University of Colorado Computation on modern hardware is a complex system. This work uses traditional nonlinear time series analysis techniques to understand the dynamics of real hardware. Our efforts have shown the first experimental evidence of chaos in computer systems and as such provides a deeper understanding of the inner workings of modern hardware. We hope these techniques will allow us to collect high-fidelity data from a running system without perturbing the system's true behavior.
	Dynamics of Social Collaborative Systems Collaborators Ed Chi: Xerox' PARC Niki Kittur : CMU This work was done while I was a summer intern at Xerox' PARC. We used information theory as a means to analyze the dynamics of social tagging systems. Our results show that over time, a social tagging site like del.icio.us is becoming harder and harder to navigate. The tagging environment is becoming saturated. We generated a bit of press: USAToday Nature News: The more, the wikier

Publications

Conference Publications

• Experimental Evidence of Chaotic Behavior in Computer Hardware
  Todd Mytkowicz, Elizabeth Bradley, and Amer Diwan
  Under review - 2008
  Also available as Department of Computer Science Technical Report CU-CS-1031-07.
• Augmented Social Cognition
  Ed H. Chi, Peter Pirolli, Bongwon Suh, Aniket Kittur, Bryan Pendleton, Todd Mytkowicz
  In Proceedings of AAAI Spring Symposium on Social Information Processing. AAAI Press, 2008
• Understanding the Efficiency of Social Tagging Systems using Information Theory
  Ed H. Chi and Todd Mytkowicz
  ACM Conference on Hypertext and Hypermedia (Hypertext 2008)
• Time Interpolation: So Many Metrics, So Few Registers
  Todd Mytkowicz, Peter F. Sweeney, Matthias Hauswirth, and Amer Diwan
  IEEE/ACM International Symposium on Microarchitecture (MICRO 2007)
• Evolving cooperative strategies for UAV teams
  Marc D. Richards, L. Darrell Whitley, J. Ross Beveridge, Todd Mytkowicz, Duong Nguyen, David Rome
  Genetic and Evolutionary Computation Conference, GECCO - 2005
• Achieving robust neural representations: An account of repetition suppression.
  Mozer, M. C., Mytkowicz, T., & Zemel, R. S.
  Unpublished Manuscript - 2004
• How Practice Makes Perfect.
  Mozer, M. C., Colagrosso, M., Huber, D. E., Mytkowicz, T., Zemel, R. S.
  Invited Talk: International Conference on Cognitive Modeling - 2004

Workshop Publications

• Understanding the Efficiency of Social Tagging Systems using Information Theory
  Ed H. Chi and Todd Mytkowicz
  International Conference on Weblogs and Social Media (ICWSM 2008)
• We have it easy, but do we have it right?
  Todd Mytkowicz, Amer Diwan, Matthias Hauswirth, and Peter F. Sweeney
  NSF Next Generation Systems Workshop - NFS/NGS 2008
• Understanding Measurement Perturbation in Trace-Based Data
  Todd Mytkowicz, Amer Diwan, Matthias Hauswirth, and Peter F. Sweeney
  NSF Next Generation Systems Workshop - NFS/NGS 2007
• Aligning traces for performance evaluation
  Todd Mytkowicz, Amer Diwan, Matthias Hauswirth, and Peter F. Sweeney
  NSF Next Generation Systems Workshop - NFS/NGS 2006

Conference Abstracts, Presentations and Posters

• Understanding Navigability of Social Tagging Systems
  Ed Chi and Todd Mytkowicz
  SIGCHI alt.chi - 2007
• Augmented Social Cognition: Understanding Social Foraging and Social Sensemaking
  Chi, E.H., Kittur, A. Mytkowicz, T., Pendleton, B., Bongwon, S.
  Presentation, Human Computer Interaction Consortium - HCIC 2007
• Power of the Few vs. Wisdom of the Crowd: Wikipedia and the Rise of the Bourgeoisie.
  Kittur, A., Chi, E., Pendleton, B. A., Suh, B., Mytkowicz, T.
  SIGCHI alt.chi - 2007
• Dynamics of Real and Simulated Computers
  Todd Mytkowicz, Elizabeth Bradley, Matthias Hauswirth, and Amer Diwan
  Poster, SIAM - Conference on Applications of Dynamical Systems - 2007
• The Relation between Activation and Computation in Functional Neuro-Imaging
  Mozer, M. C., Farah, M. Mytkowicz, T.
  Poster, Cognitive Neuroscience Society - 2004

Downloads

• ocamlgp.tar.bz2: A simple genetic programming framework for the ocaml programming language. This code is an alpha release. It is stable, however has been tested only in a limited manner. The included main.ml file contains two examples. Future work includes adding conditionals and lazy evaluation.
• planner.tar.bz2: This is a simple strips style Iterative Deepening World Space planner. It is of course written in Ocaml :). The included main.ml file shows a simple example of how to use this code.
• neural.ml,neural2.ml, and matrix.ml: The attached are neural networks for the ocaml programming language. They have been optimized for speed.

Fun

A pet project of mine has been to create artwork using dynamical systems as templates for creative, interesting pictures. My most recent attempts have been using the Lorenz Attractor and a raytracing tool named povray. Here is my first cut at this attractor. I will add more as time allows. Enjoy!