  Quasielectrons and quasiholes in the fractional quantum Hall liquids obey
fractional (including nontrivial mutual) exclusion statistics. Their statistics
matrix can be determined from several possible state-counting scheme, involving
different assumptions on statistical correlations. Thermal activation of
quasiparticle pairs and thermodynamic properties of the fractional quantum Hall
liquids near fillings $1/m$ ($m$ odd) at low temperature are studied in the
approximation of generalized ideal gas. The existence of hierarchical states in
the fractional quantum Hall effect is shown to be a manifestation of the
exclusonic nature of the relevant quasiparticles. For magnetic properties, a
paramagnetism-diamagnetism transition appears to be possible at finite
temperature.
