Abstract
We present a technique to prove lower bounds for on-line geometric searching problems. It is assumed that a goal which has to be found by a searcher is hidden somewhere in a known environment. The search cost is proportional to the distance traveled by the searcher. We are interested in lower bounds on the competitive ratio, that is, the ratio of the distance traveled by the searcher to the length of the shortest possible path to reach the goal. The technique we present is applicable to a number of problems, such as biased searching on m rays, and searching in θ-streets. For each of these problems we prove lower bounds for large classes of search strategies. All our lower bounds match the best known upper bounds.
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© 1997 Springer-Verlag Berlin Heidelberg
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Schuierer, S. (1997). Lower bounds in on-line geometric searching metric searching. In: Chlebus, B.S., Czaja, L. (eds) Fundamentals of Computation Theory. FCT 1997. Lecture Notes in Computer Science, vol 1279. Springer, Berlin, Heidelberg. https://doi.org/10.1007/BFb0036204
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DOI: https://doi.org/10.1007/BFb0036204
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