Title
Approximation Algorithms for Orienteering and Discounted-Reward TSP
Abstract
In this paper, we give the first constant-factor approximation algorithm for the rooted Orienteering problem, as well as a new problem that we call the Discounted-Reward TSP, motivated by robot navigation. In both problems, we are given a graph with lengths on edgesand prizes (rewards) on nodes, and a start node s. In the Orienteering Problem, the goal is to find a path that maximizes the reward collected, subject to a hard limit on the total length of the path. In the Discounted-Reward TSP, instead of a length limit we are given a discountfactor 驴, and the goal is to maximize total discounted reward collected, where reward for a node reached at time t is discounted by 驴t. This is similar to the objective considered in Markov Decision Processes (MDPs) except we only receive a reward the first time a node is visited. We also consider tree and multiple-path variants of these problems and provide approximations for those as well. Although the unrooted orienteering problem, where there is no fixed start node s, has been known to be approximable using algorithms for related problems such as k-TSP (in which the amount of reward to be collected is fixed and the total length is approximately minimized), ours is the first to approximate the rooted question, solving an open problem [3, 1].
Year
DOI
Venue
2007
10.1137/050645464
SIAM Journal on Computing
Keywords
DocType
Volume
unrooted orienteering problem,nonrepeatable reward,total length,fixed start node,total discounted reward,open problem,rooted orienteering problem,salesman problem,discounted-reward tsp,approximation algorithms,new problem,orienteering problem,start node,related problem,planning problem,decision trees,state space,approximation theory,markov decision process
Journal
37
Issue
ISSN
ISBN
2
0097-5397
0-7695-2040-5
Citations 
PageRank 
References 
114
6.37
15
Authors
6
Search Limit
100114
Name
Order
Citations
PageRank
Avrim Blum17978906.15
Shuchi Chawla21872186.94
David R. Karger3193672233.64
Terran Lane472377.21
Adam Meyerson52132146.08
Maria Minkoff631019.51