83 research outputs found
Explicit constructions of point sets and sequences with low discrepancy
In this article we survey recent results on the explicit construction of
finite point sets and infinite sequences with optimal order of
discrepancy. In 1954 Roth proved a lower bound for the
discrepancy of finite point sets in the unit cube of arbitrary dimension. Later
various authors extended Roth's result to lower bounds also for the
discrepancy and for infinite sequences. While it was known
already from the early 1980s on that Roth's lower bound is best possible in the
order of magnitude, it was a longstanding open question to find explicit
constructions of point sets and sequences with optimal order of
discrepancy. This problem was solved by Chen and Skriganov in 2002 for finite
point sets and recently by the authors of this article for infinite sequences.
These constructions can also be extended to give optimal order of the
discrepancy of finite point sets for . The
main aim of this article is to give an overview of these constructions and
related results
The inverse of the star-discrepancy problem and the generation of pseudo-random numbers
The inverse of the star-discrepancy problem asks for point sets of
size in the -dimensional unit cube whose star-discrepancy
satisfies where
is a constant independent of and . The first existence results in this
direction were shown by Heinrich, Novak, Wasilkowski, and Wo\'{z}niakowski in
2001, and a number of improvements have been shown since then. Until now only
proofs that such point sets exist are known. Since such point sets would be
useful in applications, the big open problem is to find explicit constructions
of suitable point sets .
We review the current state of the art on this problem and point out some
connections to pseudo-random number generators
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