Again, random numbers fall mainly in the planes: xorshift128+ generators

TL;DR

This paper investigates xorshift128+ pseudo-random number generators, revealing that their 3D output points tend to concentrate on planes, which compromises their randomness quality.

Contribution

The study demonstrates that certain parameter choices in xorshift128+ generators lead to non-uniform distributions, highlighting potential issues in their randomness.

Findings

Points in 3D plots concentrate on planes

Standard generators in platforms like JavaScript V8 are affected

Randomness quality is compromised by parameter choices

Abstract

Xorshift128+ are pseudo random number generators with eight sets of parameters. Some of them are standard generators in many platforms, such as JavaScript V8 Engine. We show that in the 3D plots generated by this method, points concentrate on planes, ruining the randomness.