Discrete Mathematics & Theoretical Computer Science, Vol 8 (2006)

Font Size:  Small  Medium  Large
DMTCS vol 8 no 1 (2006), pp. 97-120

DMTCS

Volume 8

n° 1 (2006), pp. 97-120

author:Ed Hong
title:The Online Specialization Problem
keywords:online algorithms, competitive analysis, specializations
abstract:We study the online specialization problem, where items arrive in an online fashion for processing by one of
n
different methods. Each method has two costs: a processing cost (paid once for each item processed), and a set-up cost (paid only once, on the method's first use). There are
n
possible types of items; an item's type determines the set of methods available to process it. Each method has a different degree of specialization. Highly specialized methods can process few item types while generic methods may process all item types. This is a generalization of ski-rental and closely related to the capital investment problem of Y. Azar, Y. Bartal, E. Feuerstein, A. Fiat, S. Leonardi, and A. Rosen. On capital investment. In Algorithmica, 25(1):22\u201336, 1999.. We primarily study the case where method
i+1
is always more specialized than method
i
and the set-up cost for a more specialized method is always higher than that of a less specialized method. We describe an algorithm with competitive ratio
O(log(n))
, and also show an
Ω(log(n))
lower bound on the competitive ratio for this problem; this shows our ratio is tight up to constant factors.
  If your browser does not display the abstract correctly (because of the different mathematical symbols) you may look it up in the PostScript or PDF files.
reference: Ed Hong (2006), The Online Specialization Problem, Discrete Mathematics and Theoretical Computer Science 8, pp. 97-120
bibtex:For a corresponding BibTeX entry, please consider our BibTeX-file.
ps.gz-source:dm080106.ps.gz (129 K)
ps-source:dm080106.ps (316 K)
pdf-source:dm080106.pdf (286 K)

The first source gives you the `gzipped' PostScript, the second the plain PostScript and the third the format for the Adobe accrobat reader. Depending on the installation of your web browser, at least one of these should (after some amount of time) pop up a window for you that shows the full article. If this is not the case, you should contact your system administrator to install your browser correctly.

Due to limitations of your local software, the two formats may show up differently on your screen. If eg you use xpdf to visualize pdf, some of the graphics in the file may not come across. On the other hand, pdf has a capacity of giving links to sections, bibliography and external references that will not appear with PostScript.


Automatically produced on Thu Apr 6 22:36:20 CEST 2006 by falk