We consider the following recurrence relation with random i.i.d. coefficients (an, bn):x n+1 = a n+1 xn + b n+1 where an ∈ GL(d, R), bn ∈ R d . Under natural conditions on (an, bn) this equation has a unique stationary solution, and its support is non-compact. We show that, in general, its law has a heavy tail behavior and we study the corresponding directions. This provides a natural construction of laws with heavy tails in great generality. Our main result extends to the general case the results previously obtained by H. Kesten in [16] under positivity or density assumptions, and the results recently developed in [17] in a special framework.1. Notation and problem
General notationWe consider the d-dimensional vector space V = R d , endowed with the scalar product Let G = GL(V ) be the general linear group, and H = Af f (V ) the affine group. An element h ∈ H can be written in the formwhere a ∈ G, b ∈ V . In reduced form we write h = (b, a) and we observe that the projection map (b, a) → a is a homomorphism from H to G. We consider also the projection (b, a) → b of H on V and we observe that H can be written as a semi-direct product H = G ⋉ V where V denotes also the translation group of V .For a locally compact second countable (l.c.s.c.) space X, we denote by M 1 (X) the convex set of probability measures on X and we endow M 1 (X) with the weak