Generic Analyzer

The "generic analyzer" (GA) tool is a program available on all local machines, allowing rapid statistical analysis of typical simulation data.

Overview

Data files are expected to be arranged in columns, and the GA will provide the average of each column, along with its standard deviation and correlation coefficient. As a rule of thumb, if the correlation coefficient is above 0.1, the data are consider correlated and the standard deviation is underestimated. This is typical for simulation data when sampling takes place more often than the autocorrelation time. To address this, GA will group the data in blocks and make another pass. The number of data points is now decreased, generally reducing the correlation coefficient.

General usage

When reading the output for a given column, start at the top, and go down until you have reached the first estimate for which the correlation coefficient is less than 0.1. This line provides the proper estimate of the standard deviation. To easily find this line, it is marked by a "<" at the end. Note that the correlation time can be different for different columns. The summary printed at the end of the output provide the average of each column along with the correct standard deviation and the number of independent samples. If the data in a certain column are not decorrelated even at the most coarse blocking level, a warning is issued.