Locality and Statistical Error Reduction on Correlation Functions

Locality and Statistical Error Reduction on Correlation Functions

We propose a multilevel Monte-Carlo scheme, applicable to local actions, which is expected to reduce statistical errors on correlation functions. We give general arguments to show how the efficiency and parameters of the algorithm are determined by the lowenergy spectrum. As an application, we measure the euclidean-time correlation of pairs of Wilson loops in SU(3) pure gauge theory with consta...

Locality and exponential error reduction in numerical lattice gauge theory

In non-abelian gauge theories without matter fields, expectation values of large Wilson loops and loop correlation functions are difficult to compute through numerical simulation, because the signal-to-noise ratio is very rapidly decaying for increasing loop sizes. Using a multilevel scheme that exploits the locality of the theory, we show that the statistical errors in such calculations can be...

Error Correlation and Error Reduction in Ensemble Classifiers

Using an ensemble of classi ers, instead of a single classi er, can lead to improved generalization. The gains obtained by combining however, are often a ected more by the selection of what is presented to the combiner, than by the actual combining method that is chosen. In this paper we focus on data selection and classi er training methods, in order to \prepare" classi ers for combining. We r...

On the Link between Error Correlation and Error Reduction in Decision Tree Ensembles

Recent work has shown that learning an ensemble consisting of multiple models and then making classiications by combining the classiications of the models often leads to more accurate classiications then those based on a single model learned from the same data. However, the amount of error reduction achieved varies from data set to data set. This paper provides empirical evidence that there is ...

Time-Dependent Statistical Mechanics 12. Quantum correlation functions