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An Improved LP-based Approximation for Steiner Tree

Publications associées (77)

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The standard LP relaxation of the asymmetric traveling salesman problem has been conjectured to have a constant integrality gap in the metric case. We prove this conjecture when restricted to shortest path metrics of node-weighted digraphs. Our arguments a ...

IEEE Computer Society2015

Improving Christofides' Algorithm for the s-t Path TSP

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We present a deterministic (1+root 5/2)-approximation algorithm for the s-t path TSP for an arbitrary metric. Given a symmetric metric cost on n vertices including two prespecified endpoints, the problem is to find a shortest Hamiltonian path between the t ...

Assoc Computing Machinery2015

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We study the maximum budgeted allocation problem, i.e., the problem of selling a set of m indivisible goods to n players, each with a separate budget, such that we maximize the collected revenue. Since the natural assignment LP is known to have an integral ...

Springer Heidelberg2015

Sparse Group Covers and Greedy Tree Approximations

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Springer Int Publishing Ag2015

Node-weighted network design and maximum sub-determinants

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We consider the Node-weighted Steiner Forest problem on planar graphs. Demaine et al. showed that a generic primal-dual algorithm gives a 6-approximation. We present two different proofs of an approximation factor of~

3

. Then, we draw a connection to Goem ...

EPFL2014

Coding Structure and Replication Optimization for Interactive Multiview Video Streaming

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Multiview video refers to videos of the same dynamic 3-D scene captured simultaneously by multiple closely spaced cameras from different viewpoints. We study interactive streaming of pre-encoded multiview videos, where, at any time, a client can request an ...

Ieee-Inst Electrical Electronics Engineers Inc2014

On the Configuration LP for Maximum Budgeted Allocation

Ola Nils Anders Svensson, Christos Kalaitzis, Lukas Polacek, Aleksander Madry

We study the Maximum Budgeted Allocation problem, i.e., the problem of selling a set of m indivisible goods to n players, each with a separate budget, such that we maximize the collected revenue. Since the natural assignment LP is known to have an integral ...

Springer2014

Steiner Tree Approximation via Iterative Randomized Rounding

Thomas Rothvoss, Laura Sanità

The Steiner tree problem is one of the most fundamental NP-hard problems: given a weighted undirected graph and a subset of terminal nodes, find a minimum-cost tree spanning the terminals. In a sequence of papers, the approximation ratio for this problem w ...

Assoc Computing Machinery2013

Node-weighted network design and maximum sub-determinants

Carsten Moldenhauer

3

. Then, we draw a connection to Goem ...

EPFL2014