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arXiv · 2210.13854

An Improved Algorithm for Open Online Dial-a-Ride

Julia Baligacs·Yann Disser·Nils Mosis·David Weckbecker
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Abstract

We consider the open online dial-a-ride problem, where transportation requests appear online in a metric space and need to be served by a single server. The objective is to minimize the completion time until all requests have been served. We present a new, parameterized algorithm for this problem and prove that it attains a competitive ratio of $1 + \varphi \approx 2.618$ for some choice of its parameter, where $\varphi$ is the golden ratio. This improves the best known bounds for open online dial-a-ride both for general metric spaces as well as for the real line. We also give a lower bound of~$2.457$ for the competitive ratio of our algorithm for any parameter choice.

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Julia Baligacs, Yann Disser, Nils Mosis, David Weckbecker. 2022-10-25. An Improved Algorithm for Open Online Dial-a-Ride. https://doi.org/10.1007/978-3-031-18367-6_8

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