Online Selection of Intervals and t-Intervals

  • Unnar Th. Bachmann
  • Magnús M. Halldórsson
  • Hadas Shachnai
Part of the Lecture Notes in Computer Science book series (LNCS, volume 6139)


A t-interval is a union of at most t half-open intervals on the real line. An interval is the special case where t = 1. Requests for contiguous allocation of a linear resource can be modeled as a sequence of t-intervals. We consider the problems of online selection of intervals and t-intervals, which show up in Video-on-Demand services, high speed networks and molecular biology, among others. We derive lower bounds and (almost) matching upper bounds on the competitive ratios of randomized algorithms for selecting intervals, 2-intervals and t-intervals, for any t > 2. While offline t-interval selection has been studied before, the online version is considered here for the first time.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2010

Authors and Affiliations

  • Unnar Th. Bachmann
    • 1
  • Magnús M. Halldórsson
    • 1
  • Hadas Shachnai
    • 2
  1. 1.School of Computer ScienceReykjavik UniversityReykjavikIceland
  2. 2.Department of Computer ScienceThe TechnionHaifaIsrael

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