Identification of infinite loop spaces arising from group theory Kathryn Lesh Let F_{n} be a family of subgroups of \Sigma_{n} which is closed under taking subgroups and conjugates. Such a family has a classifying space, BF_{n}, and we showed in an earlier work that a compatible choice of F_{n} for each n gives a simplicial monoid \coprod_{n} BF_{n} which group completes to an infinite loop space. In this paper we define a filtration of the associated spectrum whose filtration quotients, given an extra condition on the families, can be identified in terms of the classifying spaces of the families of subgroups that were chosen. This gives a way to go from group theoretic data about the families to homotopy theoretic information about the associated spectrum. We calculate two examples. The first is related to elementary abelian p-groups, and the second gives a new expression for the desuspension of quotients of symmetric powers of spheres as suspension spectra. Address: Department of Mathematics, University of Toledo, Toledo OH 43606 20 Aug 97 - 20 Aug 98: Department of Mathematics, Room 2-235, MIT, Cambridge, MA 02139