Frédéric Bimbot, Ivan Magrin-Chagnolleau and Luc Mathan.
Second-Order Statistical Measures for Text-Independent Speaker Identification.
Speech Communication, Vol. 17, No. 1-2, pp. 177-192, August 1995.

Abstract: This article presents an overview of several measures for speaker
recognition. These measures relate to second-order statistical tests, and
can be expressed under a common formalism. Alternate formulations of these
measures are given and their mathematical properties are studied. In their
basic form, these measures are asymmetric, but they can be symmetrized in
various ways. All measures are tested in the framework of text-independent
closed-set speaker identification, on 3 variants of the TIMIT database (630
speakers) : TIMIT (high quality speech), FTIMIT (a restricted bandwidth
version of TIMIT) and NTIMIT (telephone quality). Remarkable performances
are obtained on TIMIT but the results naturally deteriorate with FTIMIT and
NTIMIT. Symmetrization appears to be a factor of improvement, especially when
little speech material is available. The use of some of the proposed measures
as a reference benchmark to evaluate the intrinsic complexity of a given
database under a given protocol is finally suggested as a conclusion to this
work.