Table 3 CPC of the three models when dealing with outgoing mobility. Differently from the incoming mobility, the outgoing mobility before the introduction of non-pharmaceutical interventions can be modeled with all the three approaches with similar performances. However, in the second period, the performances of the radiation model raise up to a CPC of 0.815 while both the gravity models’ performances decrease to 0.183 and 0.254. Concerning IG, the best performances are reached by R (4.732) followed by G-Pow (11.386) and G-Exp (12.549)

From: Modeling international mobility using roaming cell phone traces during COVID-19 pandemic