Edited by author 05-02-2002 03:28 PM

Dave: Two URLs:

http://documents.wolfram.com/v4/MainBook/DotEqual.html

http://www.wsu.edu/~brians/errors/flesh.html

I  empathize  with  your  mere  mathematical  mortality   (lovely
alliteration!).  The  authors lost me early on, in the definition
of dynamic texture on page 3. Statements of  the  form  ``we  say
that  A  is  a  B  if  there exists a set of C and a D such that,
calling E dotequal F we have E = G with H an I from  D  for  some
choice of J, K and initial condition L'' tend to throw me.

I found equally frustrating their tendency to  introduce  symbols
without  specifying  their  intended  meanings. Perhaps these are
conventional in this  field,  but  I  had  trouble  pinning  down
exactly  what roles were played by w(t), p_w(t), y(t), x(t), A_i,
B, and {Theta}.

Yet another obstacle to my understanding is my unfamiliarity with
the  terminology.  Here's  a  quick  rundown  of things which are
meaningless to  me:  second-order  process,  Lambertian,  albedo,
first-order  ARMA,  spatial filters, auto-regressive, script-L^2,
infinite-dimensional   manifold   of    probability    densities,
Riemannian   metric,  Fisher's  Information  matrix,  first-order
Gauss-Markov models, and the enigmatic phrase ``in the  sense  of
Frobenius''.  (Who  is  this  Frobenius? I didn't find him in the
references.)

I am pleased this is the fourth consecutive  paper  to  reference
Kullback-Leibler divergence. Go KL!