We present in this paper an extended overview of the Hermite Normality
test. This test makes use of the Hermite polynomials and a modified s
phericity statistic to determine whether a unidimensional, standardise
d and white sample is normal or not. Its major advantage is to yield n
ot a single test but a real class of test statistics which allows us t
o match the normality test to the data. We give the limit distribution
of the Hermite tests both for the null and nonnull hypothesis and esp
ecially for those built with two polynomials. We have determined the t
ests asymptotically the most powerful for some fixed alternative distr
ibutions and made extensive simulations to compare the Hermite tests w
ith three others. The results are good and encourage us to go further
with the generalisation of the Hermite test to correlated and multivar
iate data. (C) 1998 Published by Elsevier Science B.V. All rights rese
rved.