The limit shape of random permutations with polynomially growing cycle weights

In this work we are considering the behaviour of the limit shape of Young diagrams associated to random permutations on the set {1,..., n} un-der a particular class of multiplicative measures with polynomial growing cycle weights. Our method is based on generating functions and complex analysis (saddle point method). We show that fluctuations near a point behave like a normal random variable and that the joint fluctuations at different points of the limiting shape have an unexpected dependence structure. We will also compare our approach with the so-called randomization of the cycle counts of permu-tations and we will study the convergence of the limit shape to a continuous stochastic process