Algebraic tools in statistics have recently been receiving special attention
and a number of interactions between algebraic geometry and computational
statistics have been rapidly developing. This paper presents another such
connection, namely, one between probabilistic models invariant under a finite
group of (non-singular) linear transformations and polynomials invariant under
the same group. Two specific aspects of the connection are discussed:
generalization of the (uniqueness part of the multivariate) problem of moments
and log-linear, or toric, modeling by expansion of invariant terms. A
distribution of minuscule subimages extracted from a large database of natural
images is analyzed to illustrate the above concepts.Comment: Published in at http://dx.doi.org/10.3150/07-BEJ6144 the Bernoulli
(http://isi.cbs.nl/bernoulli/) by the International Statistical
Institute/Bernoulli Society (http://isi.cbs.nl/BS/bshome.htm