Santosh S. Vempala
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Curriculum Vitae
Curriculum Vitae Prof. Michal Feldman School of Computer Science, Tel-Aviv University Personal Details • Born: Israel, 1976 • Gender: Female • email: [email protected] Education • Ph.D.: Information Management and Systems, University of California at Berkeley, May 2005. Thesis title: Incentives for cooperation in peer-to-peer systems. • B.Sc.: Bar-Ilan University, Computer Science, Summa Cum Laude, June 1999. Academic Positions 2013 - present: Associate Professor, School of Computer Science, Tel-Aviv University, Israel. Associate Professor, School of Business Administration and Center for 2011 - 2013: the Study of Rationality, Hebrew University of Jerusalem, Israel. 2007 - 2011: Senior Lecturer, School of Business Administration and Center for the Study of Rationality, Hebrew University of Jerusalem, Israel. Additional Positions 2011 - 2013: Visiting Researcher (weekly visitor), Microsoft Research New England, Cambridge, MA, USA. 2011 - 2013: Visiting Professor, Harvard School of Engineering and Applied Sciences, Center for Research on Computation and Society, School of Computer Science, Cambridge, MA, USA (Marie Curie IOF program). 2008 - 2011: Senior Researcher (part-time), Microsoft Research in Herzliya, Israel. 2007 - 2013: Member, Center for the Study of Rationality, Hebrew University. 2005 - 2007: Post-Doctoral Fellow (Lady Davis fellowship), Hebrew University, School of Computer Science and Engineering. 2004: Ph.D. Intern, HP Labs, Palo Alto, California, USA. 1 Grants (Funding ID) • European Research Council (ERC) Starting Grant: \Algorithmic Mechanism Design - Beyond Truthfulness": 1.4 million Euro, 2013-2017. • FP7 Marie Curie International Outgoing Fellowship (IOF): \Innovations in Algorithmic Game Theory" (IAGT): 313,473 Euro, 2011-2014. • Israel Science Foundation (ISF) grant. \Equilibria Under Coalitional Covenants in Non-Cooperative Games - Existence, Quality and Computation:" 688,000 NIS (172,000 NIS /year), 2009-2013. -
How Easy Is Local Search?
JOURNAL OF COMPUTER AND SYSTEM SCIENCES 37, 79-100 (1988) How Easy Is Local Search? DAVID S. JOHNSON AT & T Bell Laboratories, Murray Hill, New Jersey 07974 CHRISTOS H. PAPADIMITRIOU Stanford University, Stanford, California and National Technical University of Athens, Athens, Greece AND MIHALIS YANNAKAKIS AT & T Bell Maboratories, Murray Hill, New Jersey 07974 Received December 5, 1986; revised June 5, 1987 We investigate the complexity of finding locally optimal solutions to NP-hard com- binatorial optimization problems. Local optimality arises in the context of local search algorithms, which try to find improved solutions by considering perturbations of the current solution (“neighbors” of that solution). If no neighboring solution is better than the current solution, it is locally optimal. Finding locally optimal solutions is presumably easier than finding optimal solutions. Nevertheless, many popular local search algorithms are based on neighborhood structures for which locally optimal solutions are not known to be computable in polynomial time, either by using the local search algorithms themselves or by taking some indirect route. We define a natural class PLS consisting essentially of those local search problems for which local optimality can be verified in polynomial time, and show that there are complete problems for this class. In particular, finding a partition of a graph that is locally optimal with respect to the well-known Kernighan-Lin algorithm for graph partitioning is PLS-complete, and hence can be accomplished in polynomial time only if local optima can be found in polynomial time for all local search problems in PLS. 0 1988 Academic Press, Inc. 1. -
Limitations and Possibilities of Algorithmic Mechanism Design By
Incentives, Computation, and Networks: Limitations and Possibilities of Algorithmic Mechanism Design by Yaron Singer A dissertation submitted in partial satisfaction of the requirements for the degree of Doctor of Philosophy in Computer Science in the Graduate Division of the University of California, Berkeley Committee in charge: Professor Christos Papadimitriou, Chair Professor Shachar Kariv Professor Scott Shenker Spring 2012 Incentives, Computation, and Networks: Limitations and Possibilities of Algorithmic Mechanism Design Copyright 2012 by Yaron Singer 1 Abstract Incentives, Computation, and Networks: Limitations and Possibilities of Algorithmic Mechanism Design by Yaron Singer Doctor of Philosophy in Computer Science University of California, Berkeley Professor Christos Papadimitriou, Chair In the past decade, a theory of manipulation-robust algorithms has been emerging to address the challenges that frequently occur in strategic environments such as the internet. The theory, known as algorithmic mechanism design, builds on the foundations of classical mechanism design from microeconomics and is based on the idea of incentive compatible pro- tocols. Such protocols achieve system-wide objectives through careful design that ensures it is in every agent's best interest to comply with the protocol. As it turns out, however, implementing incentive compatible protocols as advocated in classical mechanism design the- ory often necessitates solving intractable problems. To address this, algorithmic mechanism design focuses on designing -
Conformance Testing David Lee and Mihalis Yannakakis Bell
Conformance Testing David Lee and Mihalis Yannakakis Bell Laboratories, Lucent Technologies 600 Mountain Avenue, RM 2C-423 Murray Hill, NJ 07974 - 2 - System reliability can not be overemphasized in software engineering as large and complex systems are being built to fulfill complicated tasks. Consequently, testing is an indispensable part of system design and implementation; yet it has proved to be a formidable task for complex systems. Testing software contains very wide fields with an extensive literature. See the articles in this volume. We discuss testing of software systems that can be modeled by finite state machines or their extensions to ensure that the implementation conforms to the design. A finite state machine contains a finite number of states and produces outputs on state transitions after receiving inputs. Finite state machines are widely used to model software systems such as communication protocols. In a testing problem we have a specification machine, which is a design of a system, and an implementation machine, which is a ‘‘black box’’ for which we can only observe its I/O behavior. The task is to test whether the implementation conforms to the specification. This is called the conformance testing or fault detection problem. A test sequence that solves this problem is called a checking sequence. Testing finite state machines has been studied for a very long time starting with Moore’s seminal 1956 paper on ‘‘gedanken-experiments’’ (31), which introduced the basic framework for testing problems. Among other fundamental problems, Moore posed the conformance testing problem, proposed an approach, and asked for a better solution. -
Xi Chen: Curriculum Vitae
Xi Chen Associate Professor Phone: 1-212-939-7136 Department of Computer Science Email: [email protected] Columbia University Homepage: http://www.cs.columbia.edu/∼xichen New York, NY 10027 Date of Preparation: March 12, 2016 Research Interests Theoretical Computer Science, including Algorithmic Game Theory and Economics, Complexity Theory, Graph Isomorphism Testing, and Property Testing. Academic Training B.S. Physics / Mathematics, Tsinghua University, Sep 1999 { Jul 2003 Ph.D. Computer Science, Tsinghua University, Sep 2003 { Jul 2007 Advisor: Professor Bo Zhang, Tsinghua University Thesis Title: The Complexity of Two-Player Nash Equilibria Academic Positions Associate Professor (with tenure), Columbia University, Mar 2016 { Now Associate Professor (without tenure), Columbia University, Jul 2015 { Mar 2016 Assistant Professor, Columbia University, Jan 2011 { Jun 2015 Postdoctoral Researcher, Columbia University, Aug 2010 { Dec 2010 Postdoctoral Researcher, University of Southern California, Aug 2009 { Aug 2010 Postdoctoral Researcher, Princeton University, Aug 2008 { Aug 2009 Postdoctoral Researcher, Institute for Advanced Study, Sep 2007 { Aug 2008 Honors and Awards SIAM Outstanding Paper Award, 2016 EATCS Presburger Award, 2015 Alfred P. Sloan Research Fellowship, 2012 NSF CAREER Award, 2012 Best Paper Award The 4th International Frontiers of Algorithmics Workshop, 2010 Best Paper Award The 20th International Symposium on Algorithms and Computation, 2009 Xi Chen 2 Silver Prize, New World Mathematics Award (Ph.D. Thesis) The 4th International Congress of Chinese Mathematicians, 2007 Best Paper Award The 47th Annual IEEE Symposium on Foundations of Computer Science, 2006 Grants Current, Natural Science Foundation, Title: On the Complexity of Optimal Pricing and Mechanism Design, Period: Aug 2014 { Jul 2017, Amount: $449,985. -
Satisfiability and Evolution
2014 IEEE Annual Symposium on Foundations of Computer Science Satisfiability and Evolution Adi Livnat Christos Papadimitriou Aviad Rubinstein Department of Biological Sciences Computer Science Division Computer Science Division Virginia Tech. University of California at Berkeley University of California at Berkeley [email protected] [email protected] [email protected] Gregory Valiant Andrew Wan Computer Science Department Simons Institute Stanford University University of California at Berkeley [email protected] [email protected] Abstract—We show that, if truth assignments on n variables genes are able to efficiently arise in polynomial populations reproduce through recombination so that satisfaction of a par- with recombination. In the standard view of evolution, a ticular Boolean function confers a small evolutionary advan- variant of a particular gene is more likely to spread across tage, then a polynomially large population over polynomially many generations (polynomial in n and the inverse of the initial a population if it makes its own contribution to the overall satisfaction probability) will end up almost surely consisting fitness, independent of the contributions of variants of other exclusively of satisfying truth assignments. We argue that this genes. How can complex, multi-gene traits spread in a theorem sheds light on the problem of the evolution of complex population? This may seem to be especially problematic adaptations. for multi-gene traits whose contribution to fitness does not Keywords-evolution; algorithms; Boolean functions decompose into small additive components associated with each gene variant —traits with the property that even if I. INTRODUCTION one gene variant is different from the one that is needed The TCS community has a long history of applying its for the right combination, there is no benefit, or even a net perspectives and tools to better understand the processes negative benefit. -
Avrim Blum, John Hopcroft, Ravindran Kannan
Foundations of Data Science This book provides an introduction to the mathematical and algorithmic founda- tions of data science, including machine learning, high-dimensional geometry, and analysis of large networks. Topics include the counterintuitive nature of data in high dimensions, important linear algebraic techniques such as singular value decompo- sition, the theory of random walks and Markov chains, the fundamentals of and important algorithms for machine learning, algorithms, and analysis for clustering, probabilistic models for large networks, representation learning including topic modeling and nonnegative matrix factorization, wavelets, and compressed sensing. Important probabilistic techniques are developed including the law of large num- bers, tail inequalities, analysis of random projections, generalization guarantees in machine learning, and moment methods for analysis of phase transitions in large random graphs. Additionally, important structural and complexity measures are discussed such as matrix norms and VC-dimension. This book is suitable for both undergraduate and graduate courses in the design and analysis of algorithms for data. Avrim Blum is Chief Academic Officer at the Toyota Technological Institute at Chicago and formerly Professor at Carnegie Mellon University. He has over 25,000 citations for his work in algorithms and machine learning. He has received the AI Journal Classic Paper Award, ICML/COLT 10-Year Best Paper Award, Sloan Fellowship, NSF NYI award, and Herb Simon Teaching Award, and is a fellow of the Association for Computing Machinery. John Hopcroft is the IBM Professor of Engineering and Applied Mathematics at Cornell University. He is a member National Academy of Sciences and National Academy of Engineering, and a foreign member of the Chinese Academy of Sciences. -
A Learning Theoretic Framework for Clustering with Similarity Functions
A Learning Theoretic Framework for Clustering with Similarity Functions Maria-Florina Balcan∗ Avrim Blum∗ Santosh Vempala† November 23, 2007 Abstract Problems of clustering data from pairwise similarity information are ubiquitous in Computer Science. Theoretical treatments typically view the similarity information as ground-truthand then design algorithms to (approximately) optimize various graph-based objective functions. However, in most applications, this similarity information is merely based on some heuristic; the ground truth is really the (unknown) correct clustering of the data points and the real goal is to achieve low error on the data. In this work, we develop a theoretical approach to clustering from this perspective. In particular, motivated by recent work in learning theory that asks “what natural properties of a similarity (or kernel) function are sufficient to be able to learn well?” we ask “what natural properties of a similarity function are sufficient to be able to cluster well?” To study this question we develop a theoretical framework that can be viewed as an analog of the PAC learning model for clustering, where the object of study, rather than being a concept class, is a class of (concept, similarity function) pairs, or equivalently, a property the similarity function should satisfy with respect to the ground truth clustering. We then analyze both algorithmic and information theoretic issues in our model. While quite strong properties are needed if the goal is to produce a single approximately-correct clustering, we find that a number of reasonable properties are sufficient under two natural relaxations: (a) list clustering: analogous to the notion of list-decoding, the algorithm can produce a small list of clusterings (which a user can select from) and (b) hierarchical clustering: the algorithm’s goal is to produce a hierarchy such that desired clustering is some pruning of this tree (which a user could navigate). -
Lipics-ICALP-2019-0.Pdf (0.4
46th International Colloquium on Automata, Languages, and Programming ICALP 2019, July 9–12, 2019, Patras, Greece Edited by Christel Baier Ioannis Chatzigiannakis Paola Flocchini Stefano Leonardi E A T C S L I P I c s – Vo l . 132 – ICALP 2019 w w w . d a g s t u h l . d e / l i p i c s Editors Christel Baier TU Dresden, Germany [email protected] Ioannis Chatzigiannakis Sapienza University of Rome, Italy [email protected] Paola Flocchini University of Ottawa, Canada paola.fl[email protected] Stefano Leonardi Sapienza University of Rome, Italy [email protected] ACM Classification 2012 Theory of computation ISBN 978-3-95977-109-2 Published online and open access by Schloss Dagstuhl – Leibniz-Zentrum für Informatik GmbH, Dagstuhl Publishing, Saarbrücken/Wadern, Germany. Online available at https://www.dagstuhl.de/dagpub/978-3-95977-109-2. Publication date July, 2019 Bibliographic information published by the Deutsche Nationalbibliothek The Deutsche Nationalbibliothek lists this publication in the Deutsche Nationalbibliografie; detailed bibliographic data are available in the Internet at https://portal.dnb.de. License This work is licensed under a Creative Commons Attribution 3.0 Unported license (CC-BY 3.0): https://creativecommons.org/licenses/by/3.0/legalcode. In brief, this license authorizes each and everybody to share (to copy, distribute and transmit) the work under the following conditions, without impairing or restricting the authors’ moral rights: Attribution: The work must be attributed to its authors. The copyright is retained by the corresponding authors. Digital Object Identifier: 10.4230/LIPIcs.ICALP.2019.0 ISBN 978-3-95977-109-2 ISSN 1868-8969 https://www.dagstuhl.de/lipics 0:iii LIPIcs – Leibniz International Proceedings in Informatics LIPIcs is a series of high-quality conference proceedings across all fields in informatics. -
Foundations of Data Science Avrim Blum , John Hopcroft , Ravi Kannan Frontmatter More Information
Cambridge University Press 978-1-108-48506-7 — Foundations of Data Science Avrim Blum , John Hopcroft , Ravi Kannan Frontmatter More Information Foundations of Data Science This book provides an introduction to the mathematical and algorithmic founda- tions of data science, including machine learning, high-dimensional geometry, and analysis of large networks. Topics include the counterintuitive nature of data in high dimensions, important linear algebraic techniques such as singular value decompo- sition, the theory of random walks and Markov chains, the fundamentals of and important algorithms for machine learning, algorithms, and analysis for clustering, probabilistic models for large networks, representation learning including topic modeling and nonnegative matrix factorization, wavelets, and compressed sensing. Important probabilistic techniques are developed including the law of large num- bers, tail inequalities, analysis of random projections, generalization guarantees in machine learning, and moment methods for analysis of phase transitions in large random graphs. Additionally, important structural and complexity measures are discussed such as matrix norms and VC-dimension. This book is suitable for both undergraduate and graduate courses in the design and analysis of algorithms for data. Avrim Blum is Chief Academic Oficer at the Toyota Technological Institute at Chicago and formerly Professor at Carnegie Mellon University. He has over 25,000 citations for his work in algorithms and machine learning. He has received the AI Journal Classic Paper Award, ICML/COLT 10-Year Best Paper Award, Sloan Fellowship, NSF NYI award, and Herb Simon Teaching Award, and is a fellow of the Association for Computing Machinery. John Hopcroft is the IBM Professor of Engineering and Applied Mathematics at Cornell University. -
Nikhil Srivastava
NIKHIL SRIVASTAVA Contact 1035 Evans Hall Information Department of Mathematics email: [email protected] UC Berkeley, Berkeley CA 94720. url: http://math.berkeley.edu/∼nikhil Education Yale University, New Haven, CT. May '10 Ph.D. in Computer Science. Advisor: Daniel Spielman. Dissertation: \Spectral Sparsification and Restricted Invertibility." Union College, Schenectady, NY. Jun '05 B.S., summa cum laude, Mathematics and Computer Science. Minor in English. Phi Beta Kappa ('04), George H. Catlin Prize, Resch Prize in Mathematics, Williams Prize in Computer Science, Hale Prize in English ('04). Positions Held University of California, Berkeley, Berkeley, CA. Associate Professor of Mathematics Jul'20{ Assistant Professor of Mathematics Jan'15{Jun'20 Microsoft Research, Bangalore, India. Researcher, Algorithms Group Jul'12{Dec'14 Research Intern & Visitor, Algorithms Group Jul{Sep '08 & '10 Simons Institute for the Theory of Computing, Berkeley, CA. Microsoft Research India Fellow, Big Data Program. Sep{Dec'13 Princeton University, Princeton, NJ. Postdoctoral Researcher, Computer Science Department Jan{Jun'12 Mathematical Sciences Research Institute, Berkeley, CA. Postdoctoral Member, Quantitative Geometry Program. Aug{Dec'11 Institute for Advanced Study, Princeton, NJ. Member, School of Mathematics Sep '10{Jul '11 Microsoft Research, Mountain View, CA. Research Intern, Theory Group Jun{Aug '09 Awards NAS Held Prize, 2021. Alfred P. Sloan Research Fellowship, 2016. (USD 55,000) NSF CAREER Award, 2016. (USD 420,000 approx.) SIAM George P´olya Prize, 2014. Invited speaker, International Congress of Mathematicians, Seoul, 2014. Best paper award, IEEE Symposium on Foundations of Computer Science, 2013. Teaching & Doctoral Students Advised. All at UC Berkeley. Advising Nick Ryder, PhD 2019. -
IARCS, the Indian Association for Research in Computing Science
IARCS, the Indian Association for Research in Computing Science, announces the 38th Foundations of Software Technology and Theoretical Computer Science conference at Ahmedabad University, Ahmedabad, Gujarat. The FSTTCS conference is a forum for presenting original results in foundational aspects of Computer Science and Software Technology. Representative areas include, but are not limited to, the following. ● Algorithmic Algebra ● Model Theory, Modal and Temporal ● Algorithms and Data Structures Logics ● Algorithmic Graph Theory and ● Models of Concurrent and Distributed Combinatorics Systems ● Approximation Algorithms ● Models of Timed, Reactive, Hybrid and ● Automata, Games and Formal Stochastic Systems Languages ● Parallel, Distributed and Online ● Combinatorial Optimization Algorithms ● Communication Complexity ● Parameterized Complexity ● Computational Biology ● Principles and Semantics of ● Computational Complexity Programming Languages ● Computational Geometry ● Program Analysis and Transformation ● Computational Learning ● Proof Complexity Theory ● Quantum Computing ● Cryptography and Security ● Randomness in Computing ● Data Streaming and Sublinear ● Specification, Verification, and algorithm Synthesis ● Game Theory and Mechanism ● Theorem Proving, Decision Procedures, Design Model Checking and Reactive Synthesis ● Logic in Computer Science ● Theoretical Aspects of Mobile and ● Machine Learning High-Performance Computing ● Quantum Computing Accepted Papers View the Accepted Papers. Click Here To Download PDF. Submissions Submissions