Strategies for improving the efficiency of quantum Monte Carlo calculations

TL;DR

This paper presents strategies to enhance the efficiency and accuracy of quantum Monte Carlo calculations, focusing on sampling algorithms, optimal time-step ratios, and data reblocking techniques to reduce statistical uncertainty.

Contribution

It introduces optimized sampling strategies, confirms the optimal time-step ratio in DMC, and discusses methods to remove serial correlation in data analysis.

Findings

Optimal time-step ratio of 1:4 in DMC confirmed

Reblocking effectively reduces serial correlation

Guidelines for choosing block length in data analysis

Abstract

We describe a number of strategies for minimizing and calculating accurately the statistical uncertainty in quantum Monte Carlo calculations. We investigate the impact of the sampling algorithm on the efficiency of the variational Monte Carlo method. Our finding that a relative time-step ratio of 1:4 is optimal in DMC is in agreement with the result of [J. Vrbik and S.M.Rothstein, Intern. J. Quantum Chem. 29, 461-468 (1986)]. Finally, we discuss the removal of serial correlation from data sets by reblocking, setting out criteria for the choice of block length and quantifying the effects of the uncertainty in the estimated correlation length.