How might one measure the difficulty of formulae?

[Vladimir Batagelj]

<<<-------- James Hartley-------->>>
> Many thanks for this.  Most helpful.  I will forward it on to my
> colleague!

  This afternoon I was thinking about a more sensitive measure.
  One possibility would be

  complexity =
  average depth of tree leaves   X  average degree of internal nodes

  Vlado
-- 
Vladimir Batagelj, University of Ljubljana, FMF, Department of Mathematics
  Jadranska 19, 1000 Ljubljana, Slovenia
http://vlado.fmf.uni-lj.si