| 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):22-36, 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. |
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| ps-source: | dm080106.ps (316 K) |
| pdf-source: | dm080106.pdf (286 K) |
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