Abstract
We consider the on-line dial-a-ride problem, where a server fulfills requests that arrive over time. Each request has a source, destination, and release time. We study a variation of this problem where each request also has a revenue that the server earns for fulfilling the request. The goal is to serve requests within a time limit while maximizing the total revenue. We first prove that no deterministic online algorithm can be competitive unless the input graph is complete and edge weights are unit. We therefore focus on these graphs and present a 2-competitive algorithm for this problem. We also consider two variations of this problem: (1) the input graph is complete bipartite and (2) there is a single node that is the source for every request, and present a 1-competitive algorithm for the former and an optimal algorithm for the latter. We also provide experimental results for the complete and complete bipartite graphs. Our simulations support our theoretical findings and demonstrate that our algorithms perform well under settings that reflect realistic dial-a-ride systems.
Similar content being viewed by others
Notes
Note that since \(v_{last}\) can be at most the maximum allowed revenue, this proof shows non-competitiveness for b equal to all possible revenue values.
We note that there are at least two enhancements that can improve the performance of grf without improving the competitive ratio: (1) In steps 2 and 7, instead of simply moving to the request that earns the greatest revenue, the algorithm can serve a request if there is one available while performing this move. (2) In steps 3 and 8, the algorithm can check if a request with higher revenue has been released since the previous step and if so, serve this request instead of r.
If at any time t, there is no request issued, we can generate a “dummy” request of the form (s, d, t, 0), where s and d are nodes in the input graph, since neither grf nor any optimal algorithm would accept this request.
References
Ascheuer N, Krumke S, Rambau J (2000) Online dial-a-ride problems: minimizing the completion time. In: Proceedings of the 17th international symposium on theoretical aspects of computer science. Lecture notes in computer science, vol 1770, pp 639–650
Ausiello G, Feuerstein E, Leonardi S, Stougie L, Talamo M (2001) Algorithms for the on-line traveling salesman. Algorithmica 29(4):560–581
Ausiello G, Bonifaci V, Laura L (2008) The on-line prize-collecting traveling salesman problem. Inf Process Lett 107(6):199–204
Azi N, Gendreau M, Potvin J (2012) A dynamic vehicle routing problem with multiple delivery routes. Ann Oper Res 199(1):103–112
Blum A, Chalasani P, Coppersmith D, Pulleyblank B, Raghavan P, Sudan M (1994) The minimum latency problem. In Proceedings of the 26th annual ACM symposium on theory of computing, pp 163–171
Christman A, Forcier W (2014) Maximizing revenues for on-line dial-a-ride. In: Combinatorial optimization and applications, pp. 522–534
City of Plymoth Minnesota. Plymouth metrolink dial-a-ride. http://www.plymouthmn.gov/departments/administrative-services-/transit/plymouth-metrolink-dial-a-ride
de Paepe W, Lenstra J, Sgall J, Sitters A, Stougie L (2004) Computer-aided complexity classification of dial-a-ride problems. INFORMS J Comput 16(2):120–132
Frederickson GN, Hecht MS, Kim CE (1978) Approximation algorithms for some routing problems. J Comput 7:178–193
Gendreau M, Hertz A, Laporte G (1994) A tabu search heuristic for the vehicle routing problem. Manag Sci 40(10):1276–1290
Guan DJ (1998) Routing a vehicle of capacity greater than one. Discrete Appl Math 81(1):41–57
Jaillet P, Lu X (2011) Online traveling salesman problems with flexibility. Networks 58:137–146
Jaillet P, Wagner M (2008) Generalized online routing: new competitive ratios, resource augmentation and asymptotic analyses. Oper Res 56(3):745–757
Jaillet P, Wagner M (2008) Online vehicle routing problems: a survey. In: The vehicle routing problem: latest advances and new challenges, pp 221-237
Kergosien Y, Lente C, Piton D, Billauta J-C (2011) A tabu search heuristic for the dynamic transportation of patients between care units. Eur J Oper Res 214(2):442–452
Krumke S (2004) On minimizing the maximum flow time in the online dial-a-ride problem. Networks 44:41–46
Liao C, Huang Y (2014) The covering Canadian traveller problem. Theor Comput Sci 530:80–88
Lorini S, Potvin J-Y, Zufferey N (2011) Online vehicle routing and scheduling with dynamic travel times. Comput Oper Res 38(7):1086–1090
Metropolitan Council. Transit link: dial-a-ride small bus service. https://metrocouncil.org/Transportation/Services/Transit-Link.aspx
Schilde M, Doerner K, Harti R (2011) Metaheuristics for the dynamic stochastic dial-a-ride problem with expected return transports. Comput Oper Res 38(12):1719–1730
Stagecoach Corporation. Dial-a-ride. http://stagecoach-rides.org/dial-a-ride/
Stougie L, Feuerstein E (2001) On-line single-server dial-a-ride problems. Theor Comput Sci 268(1):91–105
University of Washington. Dial-a-ride. http://www.washington.edu/facilities/transportation/uwshuttles/dar
Wen X, Xu Y, Zhang H (2012) Online traveling salesman problem with deadline and advanced information. Comput Ind Eng 63(4):1048–1053
Author information
Authors and Affiliations
Corresponding author
Additional information
A preliminary version of this work appeared in the proceedings of Conference of Combinatorial Optimization and Application, 2014.
Rights and permissions
About this article
Cite this article
Christman, A., Forcier, W. & Poudel, A. From theory to practice: maximizing revenues for on-line dial-a-ride. J Comb Optim 35, 512–529 (2018). https://doi.org/10.1007/s10878-017-0188-z
Published:
Issue Date:
DOI: https://doi.org/10.1007/s10878-017-0188-z