Matches in SemOpenAlex for { <https://semopenalex.org/work/W4308757079> ?p ?o ?g. }
Showing items 1 to 58 of
58
with 100 items per page.
- W4308757079 abstract "A long-standing conjecture for the traveling salesman problem (TSP) states that the integrality gap of the standard linear programming relaxation of the TSP is at most 4/3. Despite significant efforts, the conjecture remains open. We consider the half-integral case, in which the LP has solution values in ${0, 1/2, 1}$. Such instances have been conjectured to be the most difficult instances for the overall four-thirds conjecture. Karlin, Klein, and Oveis Gharan, in a breakthrough result, were able to show that in the half-integral case, the integrality gap is at most 1.49993. This result led to the first significant progress on the overall conjecture in decades; the same authors showed the integrality gap is at most $1.5- 10^{-36}$ in the non-half-integral case. For the half-integral case, the current best-known ratio is 1.4983, a result by Gupta et al. With the improvements on the 3/2 bound remaining very incremental even in the half-integral case, we turn the question around and look for a large class of half-integral instances for which we can prove that the 4/3 conjecture is correct. The previous works on the half-integral case perform induction on a hierarchy of critical tight sets in the support graph of the LP solution, in which some of the sets correspond to cycle cuts and the others to degree cuts. We show that if all the sets in the hierarchy correspond to cycle cuts, then we can find a distribution of tours whose expected cost is at most 4/3 times the value of the half-integral LP solution; sampling from the distribution gives us a randomized 4/3-approximation algorithm. We note that the known bad cases for the integrality gap have a gap of 4/3 and have a half-integral LP solution in which all the critical tight sets in the hierarchy are cycle cuts; thus our result is tight." @default.
- W4308757079 created "2022-11-15" @default.
- W4308757079 creator A5014157604 @default.
- W4308757079 creator A5043667154 @default.
- W4308757079 creator A5086769578 @default.
- W4308757079 date "2022-11-08" @default.
- W4308757079 modified "2023-09-28" @default.
- W4308757079 title "A 4/3-Approximation Algorithm for Half-Integral Cycle Cut Instances of the TSP" @default.
- W4308757079 doi "https://doi.org/10.48550/arxiv.2211.04639" @default.
- W4308757079 hasPublicationYear "2022" @default.
- W4308757079 type Work @default.
- W4308757079 citedByCount "0" @default.
- W4308757079 crossrefType "posted-content" @default.
- W4308757079 hasAuthorship W4308757079A5014157604 @default.
- W4308757079 hasAuthorship W4308757079A5043667154 @default.
- W4308757079 hasAuthorship W4308757079A5086769578 @default.
- W4308757079 hasBestOaLocation W43087570791 @default.
- W4308757079 hasConcept C11413529 @default.
- W4308757079 hasConcept C114614502 @default.
- W4308757079 hasConcept C118615104 @default.
- W4308757079 hasConcept C132525143 @default.
- W4308757079 hasConcept C162324750 @default.
- W4308757079 hasConcept C175859090 @default.
- W4308757079 hasConcept C25360446 @default.
- W4308757079 hasConcept C2780990831 @default.
- W4308757079 hasConcept C31170391 @default.
- W4308757079 hasConcept C33923547 @default.
- W4308757079 hasConcept C34447519 @default.
- W4308757079 hasConcept C41045048 @default.
- W4308757079 hasConceptScore W4308757079C11413529 @default.
- W4308757079 hasConceptScore W4308757079C114614502 @default.
- W4308757079 hasConceptScore W4308757079C118615104 @default.
- W4308757079 hasConceptScore W4308757079C132525143 @default.
- W4308757079 hasConceptScore W4308757079C162324750 @default.
- W4308757079 hasConceptScore W4308757079C175859090 @default.
- W4308757079 hasConceptScore W4308757079C25360446 @default.
- W4308757079 hasConceptScore W4308757079C2780990831 @default.
- W4308757079 hasConceptScore W4308757079C31170391 @default.
- W4308757079 hasConceptScore W4308757079C33923547 @default.
- W4308757079 hasConceptScore W4308757079C34447519 @default.
- W4308757079 hasConceptScore W4308757079C41045048 @default.
- W4308757079 hasLocation W43087570791 @default.
- W4308757079 hasLocation W43087570792 @default.
- W4308757079 hasOpenAccess W4308757079 @default.
- W4308757079 hasPrimaryLocation W43087570791 @default.
- W4308757079 hasRelatedWork W2229409480 @default.
- W4308757079 hasRelatedWork W2265089405 @default.
- W4308757079 hasRelatedWork W2470039556 @default.
- W4308757079 hasRelatedWork W2473022082 @default.
- W4308757079 hasRelatedWork W2619045485 @default.
- W4308757079 hasRelatedWork W2619966450 @default.
- W4308757079 hasRelatedWork W3201982285 @default.
- W4308757079 hasRelatedWork W4288715932 @default.
- W4308757079 hasRelatedWork W4290190164 @default.
- W4308757079 hasRelatedWork W4300410646 @default.
- W4308757079 isParatext "false" @default.
- W4308757079 isRetracted "false" @default.
- W4308757079 workType "article" @default.