Title
Self-Improving Algorithms
Abstract
We investigate ways in which an algorithm can improve its expected performance by fine-tuning itself automatically with respect to an unknown input distribution $\mathcal{D}$. We assume here that $\mathcal{D}$ is of product type. More precisely, suppose that we need to process a sequence $I_1,I_2,\ldots$ of inputs $I=(x_1,x_2,\ldots,x_n)$ of some fixed length $n$, where each $x_i$ is drawn independently from some arbitrary, unknown distribution $\mathcal{D}_i$. The goal is to design an algorithm for these inputs so that eventually the expected running time will be optimal for the input distribution $\mathcal{D}=\prod_i\mathcal{D}_i$. We give such self-improving algorithms for two problems: (i) sorting a sequence of numbers and (ii) computing the Delaunay triangulation of a planar point set. Both algorithms achieve optimal expected limiting complexity. The algorithms begin with a training phase during which they collect information about the input distribution, followed by a stationary regime in which the algorithms settle to their optimized incarnations.
Year
DOI
Venue
2011
10.1137/090766437
SIAM J. Comput.
Keywords
DocType
Volume
expected performance,unknown input distribution,product type,unknown distribution,optimized incarnation,delaunay triangulation,planar point set,input distribution,self-improving algorithm,self-improving algorithms,fixed length,sorting
Journal
40
Issue
ISSN
Citations 
2
SIAM Journal on Computing (SICOMP), 40(2), 2011, pp. 350-375
10
PageRank 
References 
Authors
0.47
28
6
Name
Order
Citations
PageRank
Nir Ailon1111470.74
Bernard Chazelle26848814.04
Kenneth L. Clarkson32516332.21
Ding Liu428116.53
Wolfgang Mulzer525736.08
C. Seshadhri693661.33