On class groups of random number fields

The aim of the present paper is to add, in several ways, to our understanding of the Cohen-Lenstra-Martinet heuristics on class groups of random number fields. Firstly, we point out several difficulties with the original formulation, and offer possible corrections. Secondly, we recast the heuristics in terms of Arakelov class groups of number fields. Thirdly, we propose a rigorously formulated Cohen-Lenstra-Martinet conjecture