Groups of galaxies: relationship between environment and galaxy   properties
  We analyse how the properties of galaxies in groups identified in the Sloan Digital Sky Survey depend on the environment. In particular, we study the relationship between galaxy properties and group mass and group-centric distance. Among the galaxy properties we have considered here, we find that the $g-r$ colour is the most predictive parameter for group mass, while the most predictive pair of properties are $g-r$ colour and $r-$band absolute magnitude. Regarding the position inside the systems, the $g-r$ colour is the best tracer of group-centric distance and the most predictive pair of properties are $g-r$ colour and spectral type taken together. These results remain unchanged when a subsample of high mass groups is analysed. The same happens if the brightest group galaxies are excluded. 
Hector J. Martinez and Hernan Muriel