Comparison of the UMT and GUMT models.

(Left-Panels) Frequency of occurrence n_i (suitably normalised with the maximum value n_max) of each element i ∈ S as a function of its first appearance time t_i. (Right-Panels) For each interval of length Δτ we plot of the first appearance time of the most popular element within the interval, t_max(I). The length of each interval is Δτ = 10000. Top Panels are results coming from a simulation of the UMT model with parameters ρ = 2, ν = 2 and η = 0.4 for the model. Bottom Panels correspond to simulations of the GUMT model with ρ = 2, ν = 15, η = 0.001, γ = 0.004 and the choice II of the function f and g.