STOC '94 Proceedings of the twenty-sixth annual ACM symposium on Theory of computing
Randomized algorithms
Scheduling to minimize average completion time: off-line and on-line approximation algorithms
Mathematics of Operations Research
Online computation and competitive analysis
Online computation and competitive analysis
Approximation schemes for minimum latency problems
STOC '99 Proceedings of the thirty-first annual ACM symposium on Theory of computing
Scheduling to minimize average completion time: off-line and on-line algorithms
Proceedings of the seventh annual ACM-SIAM symposium on Discrete algorithms
An improved approximation ratio for the minimum latency problem
Proceedings of the seventh annual ACM-SIAM symposium on Discrete algorithms
A guessing game and randomized online algorithms
STOC '00 Proceedings of the thirty-second annual ACM symposium on Theory of computing
On-line single-server dial-a-ride problems
Theoretical Computer Science
Improved Scheduling Algorithms for Minsum Criteria
ICALP '96 Proceedings of the 23rd International Colloquium on Automata, Languages and Programming
Two short notes on the on-line travelling salesman: handling times and lookahead
Theoretical Computer Science
Theoretical Computer Science
Discrete Applied Mathematics - Special issue: Traces of the Latin American conference on combinatorics, graphs and applications: a selection of papers from LACGA 2004, Santiago, Chile
Theoretical Computer Science - Approximation and online algorithms
Online Routing Problems: Value of Advanced Information as Improved Competitive Ratios
Transportation Science
A new formulation for the Traveling Deliveryman Problem
Discrete Applied Mathematics
New lower bounds for online k-server routing problems
Information Processing Letters
On an Online Traveling Repairman Problem with Flowtimes: Worst-Case and Average-Case Analysis
COCOON '09 Proceedings of the 15th Annual International Conference on Computing and Combinatorics
Online dial-a-ride problem with time-windows under a restricted information model
AAIM'06 Proceedings of the Second international conference on Algorithmic Aspects in Information and Management
On minimizing the maximum flow time in the online dial-a-ride problem
WAOA'05 Proceedings of the Third international conference on Approximation and Online Algorithms
On the online dial-a-ride problem with time-windows
AAIM'05 Proceedings of the First international conference on Algorithmic Applications in Management
Online k-server routing problems
WAOA'06 Proceedings of the 4th international conference on Approximation and Online Algorithms
Competitive analysis of a dispatch policy for a dynamic multi-period routing problem
Operations Research Letters
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In the traveling repairman problem (TRP), a tour must be found through every one of a set of points (cities) in some metric space such that the weighted sum of completion times of the cities is minimized. Given a tour, the completion time of a city is the time traveled on the tour before the city is reached. In the online traveling repairman problem (OLTRP) requests for visits to cities arrive online while the repairman is traveling. We analyze the performance of algorithms for the online problem using competitive analysis, where the cost of an online algorithm is compared to that of an optimal offline algorithm.We show how to use techniques from online-scheduling to obtain a deterministic algorithm with a competitive ratio of (1 + √2)2 5.8285 for the OLTRP in general metric spaces. We also present a randomized algorithm which achieves a competitive ratio of 4/ln 3 3.6410 against an oblivious adversary. Our results extend to the "dial-a-ride" generalization L-OLDARP of the OLTRP, where objects have to be picked up and delivered by a server. This improves upon the previously best competitive ratio of 9 for the OLTRP on the real line and, moreover, the results are valid for any metric space. For the case of the L-OLDARP our algorithms are the first competitive algorithms.We also derive the first lower bounds for the competitive ratio of randomized algorithms for the OLTRP and the L-OLDARP against an oblivious adversary. Our lower bounds are (ln 16 + 1)/ (ln 16 - 1) e--5)/(2e-3)