  Numerical experiments support the interesting conjecture that statistical
methods be applicable not only to fully-chaotic systems, but also at the edge
of chaos by using Tsallis' generalizations of the standard exponential and
entropy. In particular, the entropy increases linearly and the sensitivity to
initial conditions grows as a generalized exponential. We show that this
conjecture has actually a broader validity by using a large class of deformed
entropies and exponentials and the logistic map as test cases.
