Mr.  Andrew Tsai is Managing Director of PDT Partners, and the Co-Founder and Chairman of Chalkstream Capital Group. Prior to founding Chalkstream in 2003, Mr. Tsai worked as CEO of GNR Ltd, a technology infrastructure company based in London, and before that as President and Director of Urbanfetch Ltd, an internet logistics firm based in New York and London. Mr. Tsai was formerly a co-founder and the Chief Investment Officer of Integrity Capital Management, a hedge fund that employed quantitative long/short strategies in equities, fixed income, currency and commodity markets. Prior to Integrity, Mr. Tsai was a Vice President and Head of the German Government Fixed-Income Trading Operations at Lehman Brothers International (London) and also served as part of the Global Arbitrage team at Lehman Brothers Inc. (New York). Mr. Tsai graduated in 1993 from the Wharton School of Business at the University of Pennsylvania with a B.S. in Economics. Mr. Tsai serves on the board of trustees for Cancer Research Institute.