This book constitutes the joint refereed proceedings of the 15th International Workshop on Approximation Algorithms for Combinatorial Optimization Problems, APPROX 2012, and the 16th International Workshop on Randomization and Computation, RANDOM 2012, held in Cambridge, Massachusetts, USA, in August 2011. The volume contains 28 contributed papers, selected by the APPROX Program Committee out of 70 submissions, and 28 contributed papers, selected by the RANDOM Program Committee out of 67 submissions. APPROX focuses on algorithmic and complexity issues surrounding the development of efficient approximate solutions to computationally difficult problems. RANDOM is concerned with applications of randomness to computational and combinatorial problems.
A New Point of NP-Hardness for 2-to-1 Label Cover.-Inapproximability of Treewidth, One-Shot Pebbling, and Related Layout Problems .-Additive Approximation for Near-Perfect Phylogeny Construction.-Improved Spectral-Norm Bounds for Clustering.-Primal-Dual Approximation Algorithms for Node-Weighted Network Design in Planar Graphs .-What’s the Frequency, Kenneth?: Sublinear Fourier Sampling Off the Grid.-Improved Hardness Results for Profit Maximization Pricing Problems
with Unlimited Supply.-Online Flow Time Scheduling in the Presence of Preemption Overhead.-Prize-Collecting Survivable Network Design in Node-Weighted Graphs .-Approximating Minimum-Cost Connected T -Joins .-iBGP and Constrained Connectivity.-Online Scheduling of Jobs with Fixed Start Times on Related Machines .-A Systematic Approach to Bound Factor Revealing LPs and Its Application to the Metric and Squared Metric Facility Location Problems .-Approximating Bounded Occurrence Ordering CSPs .-On the NP-Hardness of Max-Not-2 .-The Remote Set Problem on Lattices .-Approximation Algorithms for Generalized and Variable-Sized Bin Covering .-Approximating Minimum Linear Ordering Problems.-New Approximation Results for Resource Replication Problems .-Maximum Matching in Semi-streaming with Few Passes .-Improved Inapproximability for TSP .-Approximation Algorithm for Non-boolean MAX k-CSP .-Planarizing an Unknown Surface.-The Projection Games Conjecture and the NP-Hardness of In n-Approximating Set-Cover.-New and Improved Bounds for the Minimum Set Cover Problem.-Hardness of Vertex Deletion and Project Scheduling.-Approximation Guarantees for the Minimum Linear Arrangement Problem by Higher Eigenvalues .-Circumventing d-to-1 for Approximation Resistance of Satisfiable Predicates Strictly Containing Parity of Width Four (Extended Abstract).-Spectral Norm of Symmetric Functions .-Almost K-Wise vs. K-Wise Independent Permutations, and Uniformity for General Group Actions.-Testing Permanent Oracles – Revisited.-Limitations of Local Filters of Lipschitz and Monotone Functions .-Testing Lipschitz Functions on Hypergrid Domains .-Extractors for Polynomials Sources over Constant-Size Fields of Small Characteristic.-Multiple-Choice Balanced Allocation in (Almost) Parallel.-Optimal Hitting Sets for Combinatorial Shapes.-Tight Bounds for Testing k-Linearity.-Pseudorandomness for Linear Length Branching Programs and Stack Machines.-A Discrepancy Lower Bound for Information Complexity.-On the Coin Weighing Problem with the Presence of Noise.-Information Complexity versus Corruption and Applications to Orthogonality and Gap-Hamming.-An Explicit VC-Theorem for Low-Degree Polynomials .-Tight Bounds on the Threshold for Permuted k-Colorability.-Sparse and Lopsided Set Disjointness via Information Theory.-Maximal Empty Boxes Amidst Random Points .-Rainbow Connectivity of Sparse Random Graphs.-Invertible Zero-Error Dispersers and Defective Memory with Stuck-At Errors .-Two-Sided Error Proximity Oblivious Testing (Extended Abstract).-Mirror Descent Based Database Privacy.-Analysis of k-Means++ for Separable Data.-A Sharper Local Lemma with Improved Applications.-Finding Small Sparse Cuts by Random Walk.-On Deterministic Sketching and Streaming for Sparse Recovery and Norm Estimation.-A New Upper Bound on the Query Complexity for Testing Generalized Reed-Muller Codes.-A Combination of Testability and Decodability by Tensor Products Extractors for Turing-Machine Sources.
