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| Preface | ||
| Prologue | ||
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   Introduction
    
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| 1. | 
   Complexity and Approximation Thomas Jansen  | 
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| 1.1 | Introduction | |
| 1.2 | Basic Definitions | |
| 1.3 | Complexity Classes for Randomized Algorithms | |
| 1.4 | 
   Optimization and Approximation
    
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| 2. | 
   Randomized Algorithms Artur Andrzejak  | 
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| 2.1 | Introduction | |
| 2.2 | Las Vegas and Monte Carlo Algorithms | |
| 2.3 | Examples of Randomized Algorithms | |
| 2.4 | Randomized Rounding of Linear Programs | |
| 2.5 | 
   A Randomized Algorithm for MAXSAT
    
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| 3. | 
   Derandomization Detlef Sieling  | 
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| 3.1 | Introduction | |
| 3.2 | The Method of Conditional Probabilities | |
| 3.3 | MAXEkSAT, MAXSAT and MAXLINEQ3-2 | |
| 3.4 | Approximation Algorithms for Linear Integer Programs | |
| 3.5 | Reduction of the Size of the Probability Space | |
| 3.6 | Another Approximation Algorithm for MAXE3SAT | |
| 3.7 | 
   A PRAM Algorithm for MAXIMALINDEPENDENTSET
    
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| 4. | 
   Proof Checking and Non-Approximability Stefan Hougardy  | 
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| 4.1 | Introduction | |
| 4.2 | Probabilistically Checkable Proofs | |
| 4.3 | PCP and Non-Approximability | |
| 4.4 | Non-Approximability of APX-Complete Problems | |
| 4.5 | Expanders and the Hardness of Approximating MAXE3SAT-b | |
| 4.6 | Non-Approximability of MAXCLIQUE | |
| 4.7 | 
   Improved Non-Approximability Results for
   MAXCLIQUE
    
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| 5. | 
   Proving the PCP-Theorem Volker Heun, Wolfgang Merkle, Ulrich Weigand  | 
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| 5.1 | Introduction and Overview | |
| 5.2 | Extended and Constant Verifiers | |
| 5.3 | Encodings | |
| 5.4 | Efficient Solution Verifiers | |
| 5.5 | Composing Verifiers and the PCP-Theorem | |
| 5.6 | The LFKN Test | |
| 5.7 | The Low Degree Test | |
| 5.8 | 
   A Proof of Cook's Theorem
    
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| 6. | 
   Parallel Repetition of MIP(2,1) Systems Clemens Gröpl, Martin Skutella  | 
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| 6.1 | Prologue | |
| 6.2 | Introduction | |
| 6.3 | Two-Prover One-Round Proof Systems | |
| 6.4 | Reducing the Error Probability | |
| 6.5 | Coordinate Games | |
| 6.6 | How to Prove the Parallel Repetition Theorem (I) | |
| 6.7 | 
   How to Prove the Parallel Repetition Theorem (II)
    
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| 7. | 
   Bounds for Approximating
   MAXLINEG3-2
   and MAXEkSAT Sebastian Seibert, Thomas Wilke  | 
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| 7.1 | Introduction | |
| 7.2 | Overall Structure of the Proofs | |
| 7.3 | Long Code, Basic Tests, and Fourier Transform | |
| 7.4 | Using the Parallel Repetition Theorem for Showing Satisfiability | |
| 7.5 | An Optimal Lower Bound for Approximating MAXLINEQ3-2 | |
| 7.6 | 
   Optimal Lower Bounds for Approximating
   MAXEkSAT
    
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| 8. | 
   Deriving Non-Approximability Results by Reductions Claus Rick, Hein Röhrig  | 
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| 8.1 | Introduction | |
| 8.2 | Constraint Satisfaction Problems | |
| 8.3 | The Quality of Gadgets | |
| 8.4 | Weighted vs. Unweighted Problems | |
| 8.5 | Gadget Construction | |
| 8.6 | 
   Improved Results
    
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| 9. | 
   Optimal Non-Approximability of
   MAXCLIQUE Martin Mundhenk, Anna Slobodová  | 
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| 9.1 | Introduction | |
| 9.2 | A PCP-System for ROBE3SAT and Its Parallel Repetition | |
| 9.3 | The Long Code and Its Complete Test | |
| 9.4 | 
   The Non-Approximability of
   MAXCLIQUE
    
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| 10. | 
   The Hardness of Approximating Set Cover Alexander Wolff  | 
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| 10.1 | Introduction | |
| 10.2 | The Multi-Prover Proof System | |
| 10.3 | Construction of a Partition System | |
| 10.4 | 
   Reduction to Set Cover
    
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| 11. | 
   Semidefinite Programming Thomas Hofmeister, Martin Hühne  | 
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| 11.1 | Introduction | |
| 11.2 | Basics from Matrix Theory | |
| 11.3 | Semidefinite Programming | |
| 11.4 | Duality and an Interior-Point Method | |
| 11.5 | Approximation Algorithms for MAXCUT | |
| 11.6 | Modeling Asymmetric Problems | |
| 11.7 | Combining Approximation Algorithms | |
| 11.8 | Improving the Approximation Ratio | |
| 11.9 | 
   Modeling Maximum Independent Set as a Semidefinite Program ?
    
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| 12. | 
   Dense Instances of Hard Optimization Problems Katja Wolf  | 
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| 12.1 | Introduction | |
| 12.2 | Motivation and Preliminaries | |
| 12.3 | Approximating Smooth Integer Programs | |
| 12.4 | MAXCUT and MAXEkSAT | |
| 12.5 | 
   Related Work
    
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| 13. | 
   Approximation Schemes for Geometric Problems Richard Mayr, Annette Schelten  | 
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| 13.1 | Introduction | |
| 13.2 | Definitions and Notations | |
| 13.3 | The Structure Theorem and Its Proof | |
| 13.4 | The Algorithm | |
| 13.5 | Applications to Some Related Problems | |
| 13.6 | 
   The Earlier PTAS
    
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| Bibliography | ||
| Author Index | ||
| Subject Index | ||
| List of Contributors | ||