In this paper we describe a Sequential Importance Sampling (SIS) procedure for counting the number of vertex covers in general graphs. The performance of SIS depends heavily on how close the SIS proposal distribution is to a uniform one over a suitably restricted set. The proposed algorithm...

This discussion paper resulted in a publication in the <I>Siam Journal on Matrix Analysis and Applications (2011). Volume 32, issue 3, pages 665-684.<P> A sequence of real numbers (<I>x_n</I>) is Benford if the significands, i.e. the fractionparts in the floating-point representation of (<I>x_n</I>), are distributed...</i></i></p></i>

This discussion paper resulted in a publication in the <I>Mathematical Methods of Operations Research</I> (2005). Volume 62, issue 3, pages 467-483.<P> We develop a methodology for studying "large deviations type" questions. Our approach does not require that the large deviations principle holds, and is...</p></i>

In: <I>Proceedings Winter Simulation Conference</I>, 9-12 December 2012, pages 387-398.<P> In rare event simulation, we look for estimators such that the relative accuracy of the output is ''controlled'' when the rarity is getting more and more critical. Different robustness properties have been defined...</p></i>

There are various importance sampling schemes to estimate rare event probabilities in Markovian systems such as Markovian reliability models and Jackson networks. In this work, we present a general state-dependent importance sampling method which partitions the state space and applies the...

We apply the splitting method to three well-known counting problems, namely 3-SAT, random graphs with prescribed degrees, and binary contingency tables. We present an enhanced version of the splitting method based on the capture-recapture technique, and show by experiments the superiority of...

We develop a methodology for studying “large deviations type” questions. Our approach does not require that the large deviations principle holds, and is thus applicable to a large class of systems. We study a system of queues with exponential servers, which share an arrival stream. Arrivals...

We develop a methodology for studying “large deviations type” questions. Our approach does not require that the large deviations principle holds, and is thus applicable to a large class of systems. We study a system of queues with exponential servers, which share an arrival stream. Arrivals...

A sequence of real numbers (<I>x_n</I>) is Benford if the significands, i.e. the fraction

A version of the classical secretary problem is studied, in which one is interested in selecting one of the <I>b</I> best out of a group of <I>n</I> differently ranked persons who are presented one by one in a random order. It is assumed that <I>b</I> is bigger than or equal to 1 is a preassigned number. It is...</i></i></i>