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, We monitored the standard deviation ?sim(t), of the simulated opinion distribution and we measured the time when the latter gets smaller than a treshold amount thr here set to 0.001 (i.e. 10 times smaller than the initial inter-particle separation.). The aggregation times thus obtained averaging over 50 indipendent runs, are Tagg ? 7100 for ?c = 0.5, Tagg ? 3000 for ?c = 0.3, and Tagg ? 1730 for ?c, absence of birth/death perturbation, ? = 0, we assumed the following stopping criterion

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