Table 3

ARIMAX model for global, US and Brazilian online trends with press releases by relevant health agency as predictors

ARIMAX modelPredictorStationary R2 Parameters of the model
Estimatep Value
Global(0,1,1)Press releases by WHO0.345MA (lag 1)−0.4330.001
Predictor13.316<0.001
USA(0,1,1)Press releases by CDC0.318MA (lag 1)−0.727<0.001
Predictor3.8690.014
Brazil(0,1,1)Press releases by MHB not a predictor0.182MA (lag 1)−0.3910.003
  • ARIMAX, AutoRegressive Integrated Moving Average with an eXogenous predictor variable; CDC, Centers for Disease Control and Prevention; MHB, Ministry of Health Brazil; WHO, World Health Organization