In this study we present theoretical concepts and results concerning the hy
pothesis test of the magnetospheric chaos. For this reason we compare the o
bservational behavior of the magnetospheric system with results obtained by
analyzing different types of stochastic and deterministic input-output sys
tems. The results of this comparison indicate that the hypothesis of low-di
mensional chaos for the magnetospheric dynamics remains a possible and frui
tful concept which must be developed further.