KISS ( Keep it Simple Stupid) is a family of

pseudorandom number generator A pseudorandom number generator (PRNG), also known as a deterministic random bit generator (DRBG), is an algorithm for generating a sequence of numbers whose properties approximate the properties of sequences of random number generation, random n ...

s introduced by George Marsaglia. Starting from 1998 Marsaglia posted on various

newsgroups A Usenet newsgroup is a repository usually within the Usenet system for messages posted from users in different locations using the Internet. They are not only discussion groups or conversations, but also a repository to publish articles, start ...

including sci.math, comp.lang.c, comp.lang.fortran and sci.stat.math several versions of the generators. All KISS generators combine three or four independent random number generators with a view to improving the quality of randomness. KISS generators produce 32-bit or 64-bit random integers, from which random floating-point numbers can be constructed if desired. The original 1993 generator is based on the combination of a

linear congruential generator A linear congruential generator (LCG) is an algorithm that yields a sequence of pseudo-randomized numbers calculated with a discontinuous piecewise linear equation. The method represents one of the oldest and best-known pseudorandom number gener ...

and of two linear feedback shift-register generators. It has a period 2⁹⁵, good speed and good statistical properties; however, it fails the LinearComplexity test in the Crush and BigCrush tests of the TestU01 suite. A newer version from 1999 is based on a linear congruential generator, a 3-shift linear feedback shift-register and two multiply-with-carry generators. It is 10–20% slower than the 1993 version but has a larger period 2¹²³ and passes all tests in TestU01. In 2009 Marsaglia presented a version based on 64-bit integers (appropriate for 64-bit processors) which combines a

multiply-with-carry In computer science, multiply-with-carry (MWC) is a method invented by George Marsaglia for generating sequences of random integers based on an initial set from two to many thousands of randomly chosen seed values. The main advantages of the MWC m ...

generator, a Xorshift generator and a linear congruential generator. It has a period of around 2²⁵⁰ (around 10⁷⁵).

References

Further reading