Showing 1 - 10 of 12
In the last 20 years competitive analysis has become the main tool for analyzing the quality of online algorithms. Despite of this, competitive analysis has also been criticized: it sometimes cannot discriminate between algorithms that exhibit significantly different empirical behavior or it...
Persistent link: https://www.econbiz.de/10011146937
It is well known that competitive analysis yields results that do not reflect the observed performance of online paging algorithms. Many deterministic paging algorithms achieve the same competitive ratio, ranging from inefficient strategies as flush-when-full to the well-performing...
Persistent link: https://www.econbiz.de/10011146954
We present constant approximative policies for preemptive stochastic scheduling. We derive policies with a guaranteed performance ratio of 2 for scheduling jobs with release dates on identical parallel machines subject to minimizing the sum of weighted completion times. Our policies as well as...
Persistent link: https://www.econbiz.de/10011146970
We consider the problem of minimizing the makespan on restricted related parallel machines. In restricted machine scheduling each job is only allowed to be scheduled on a subset of machines. We study the worst-case behavior of local search algorithms. In particular, we analyze the quality of...
Persistent link: https://www.econbiz.de/10011146980
We present first constant performance guarantees for preemptive stochastic scheduling to minimize the sum of weighted completion times. For scheduling jobs with release dates on identical parallel machines we derive policies with a guaranteed performance ratio of 2 which matches the currently...
Persistent link: https://www.econbiz.de/10011160402
We consider a stochastic scheduling problem which generalizes traditional stochastic scheduling by introducing parameter uncertainty. Two classes of independent jobs have to be processed by a single machine so as to minimize the sum of expected completion times. The processing times of the jobs...
Persistent link: https://www.econbiz.de/10011160428
This paper proposes a new method for probabilistic analysis of online algorithms that is based on the notion of stochastic dominance. We develop the method for the Online Bin Coloring problem introduced by Krumke et al. Using methods for the stochastic comparison of Markov chains we establish...
Persistent link: https://www.econbiz.de/10011160430
We consider the problem to price (digital) items in order to maximize the revenue obtainable from a set of bidders. We suggest a natural monotonicity constraint on bundle prices, show that the problem remains NP-hard, and we derive a PTAS. We also discuss a special case, the highway pricing problem.
Persistent link: https://www.econbiz.de/10011160444
We consider a stochastic scheduling problem in which there is uncertainty about parame-ters of the probability distribution of the processing times. We restrict ourselves to the setting in which there are two different classes of jobs. The processing times of the jobs are assumed to be...
Persistent link: https://www.econbiz.de/10011160454
Increasing interest has recently been shown in analyzing the worst-case behavior of local search algorithms. In particular, the quality of local optima and the time needed to find the local optima by the simplest form of local search has been studied. This paper deals with worst-case performance...
Persistent link: https://www.econbiz.de/10011160456