hello,
it's rather a remark than a question.
I set all my firescarsvalues on my satellite image to "null()" (r.mapcalc map_out=if(map_in<=x,null(),map_in) )and
calcualted mean, sd, diversity etc. with r.le.pixel. When I choose 1.5 pixel radius in the r.le.setup the output inside the
firescars which I set to null, were "0". All the calcualtion with radius 2.5, 3.5, 4.5 and 8.5 were "null()" as expected.
perhaps I am wrong but it looks like a bug .... or a stupid user 
cheers Martin
-------------------------------
Martin Wegmann
Tropical Ecosystem Research Center
PMB 44 Winnellie / Darwin
NT 0821
Australia
.......
priv.
4 Carpentier Cres.
Wagaman / Darwin
NT 0810
Autralia
0061 8 8927 1241