G_δ ideals of compact sets

We investigate the structure of G_δ ideals of compact sets. We define a class of G_δ ideals of compact sets that, on the one hand, avoids certain phenomena present among general G_δ ideals of compact sets and, on the other hand, includes all naturally occurring G_δ ideals of compact sets. We prove structural theorems for ideals in this class, and we describe how this class is placed among all G _δ ideals. In particular, we establish a result representing ideals in this class via the meager ideal. This result is analogous to Choquet's theorem representing alternating capacities of order ∞via Borel probability measures. Methods coming from the structure theory of Banach spaces are used in constructing important examples of G_δ ideals outside of our class.