  Parton distributions are constructed in a statistical physical picture of the
nucleon. The chiral properties of QCD lead to strong relations between quarks
and antiquarks distributions and the importance of the Pauli exclusion
principle is also emphasized. A global next-to-leading order QCD analysis of
unpolarized and polarized deep-inelastic scattering data is performed to
determine a small number of free parameters. Some predictions are compared to
recent experimental results. We also present an extension of the statistical
approach to the description of baryon fragmentation functions.
