We show that using Frieden and Soffer's extreme information principle [Phys
. Rev. E 52, 2274 (1995)] with a Fisher measure constructed with escort pro
babilities [C. Beck and F. Schlogel, Thermodynamics of Chaotic Systems (Cam
bridge University Press, Cambridge, England, 1993)], the concomitant soluti
ons obey a type of Naudts's duality (e-print cond-mat/990470) for nonextens
ive ensembles [C. Tsallis, in Nonextensive Statistical Mechanics and its Ap
plications, Lecture Notes in Physics, edited by S. Abe and Y. Okamoto (Spri
nger-Verlag, Berlin, in press)].