RT Journal Article T1 StringENT test suite: ENT battery revisited for efficient P value computation A1 Almaraz Luengo, Elena A1 Alaña Olivares, Bittor A1 García Villalba, Luis Javier A1 Hernandez-Castro, Julio A1 Hurley-Smith, Darren AB Random numbers play a key role in a wide variety of applications, ranging from mathematical simulation to cryptography. Generating random or pseudo-random numbers is not an easy task, especially when hardware, time and energy constraints are considered. In order to assess whether generators behave in a random fashion, there are several statistical test batteries. ENT is one of the simplest and most popular, at least in part due to its efficacy and speed. Nonetheless, only one of the tests of this suite provides a p value, which is the most useful and standard way to determine whether the randomness hypothesis holds, for a certain significance level. As a consequence of this, rather arbitrary and at times misleading bounds are set in order to decide which intervals are acceptable for its results. This paper introduces an extension of the battery, named StringENT, which, while sticking to the fast speed that makes ENT popular and useful, still succeeds in providing p values with which sound decisions can be made about the randomness of a sequence. It also highlights a flagrant randomness flaw that the classical ENT battery is not capable of detecting but the new StringENT notices, and introduces two additional tests. SN 2190-8508 YR 2023 FD 2023 LK https://hdl.handle.net/20.500.14352/73239 UL https://hdl.handle.net/20.500.14352/73239 LA eng NO 1. Kawai, R., Masuda, H.: On simulation of tempered stable random variates. J. Comput. Appl. Math. 235(8), 2873–2887 (2011).https://doi.org/10.1016/j.cam.2010.12.0142. 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