Stochastic Fluctuations in the Spectrophotometric Properties of Star   Clusters
  Integrated spectrophotometric properties of stellar systems are intrinsically dispersed due to the stochastic nature of the small numbers of bright stars they contain. Among clusters, only the most massive ones can be used individually for comparison with the mean properties predicted by population synthesis calculations. The appropriate minimal masses depend, among others, on the waveband or colour index studied and on age. Selected indices (near-IR CO and H2O, EW(Halpha)) are used to illustrate the asymmetric nature of the probability distribution of observable properties and their dependence on cluster mass. 
Ariane Lan\c{c}on, Mustapha Mouhcine (Observatoire de Strasbourg)