The Relation of Compact Groups of Galaxies with Larger-scale Structures
  We show that Compact Groups of Galaxies (CGs) are frequently associated with larger-scale structures, and such associations become more frequent for CGs selected by the same criteria at higher redshifts. Our findings suggest that CGs are an intrinsic part of the cosmological structure formation process and are consistent with the LambdaCDM (or "concordance") model, but only if galaxy formation is a biased process. 
Heinz Andernach and Roger Coziol, (Department of Astronomy,   Universidad de Guanajuato)