Package edu.cmu.tetrad.util

Class EssLikePython

java.lang.Object

edu.cmu.tetrad.util.EssLikePython

public final class EssLikePython
extends Object

The EssLikePython class provides methods for estimating the Effective Sample Size (ESS) of a dataset using procedures that closely mimic functionality found my Python script. This includes column standardization, row sampling, and computation of correlations to derive the ESS value.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static final class	EssLikePython.Result	Encapsulates the results of an estimation process, including average row correlation, effective sample size (ESS), and the number of rows used in the computation.

Constructor Summary

Constructors

Constructor	Description
EssLikePython()	Default constructor for the EssLikePython class.

Method Summary

Modifier and Type	Method	Description
static EssLikePython.Result	estimateLikePython(org.ejml.simple.SimpleMatrix X, int sampleSize, boolean clampNonnegative, Random rng)	Estimates the effective sample size (ESS) and average row correlation (avgRowCorr) from a given dataset, by column-standardizing, sampling rows, and computing row-wise correlations.

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Details

EssLikePython

public EssLikePython()

Default constructor for the EssLikePython class. Initializes a new instance of the EssLikePython class.

Method Details

estimateLikePython

public static EssLikePython.Result estimateLikePython(org.ejml.simple.SimpleMatrix X,
 int sampleSize,
 boolean clampNonnegative,
 Random rng)

Estimates the effective sample size (ESS) and average row correlation (avgRowCorr) from a given dataset, by column-standardizing, sampling rows, and computing row-wise correlations. Optionally clamps the correlation to ensure non-negativity.

Parameters:

X - the input data matrix where rows represent observations and columns represent variables

sampleSize - the number of rows to sample without replacement during the estimation process

clampNonnegative - a flag indicating whether to clamp avgRowCorr to nonnegative values

rng - a Random object to control the random sampling of rows (if null, a default seed is used)

Returns:

a Result object containing the estimated avgRowCorr, computed ESS, and the number of rows used