why are seasonal dummies important when a seasonal dummy is used in a forecast what is the significance why do seasonal dummies work why is seasonal dummy not useful what is the significance of seasonal dummies when to use seasonal dummies in forecasting how should seasonality be tested why do i exclude seasonal dummies why do i exclude seasonal dummies when do we exclude a seasonal variable from t-test do seasonal dummies have low t scores when to exclude seasonal dummies why are seasonal dummies excluded why is it necessary to use seasonal dummies in a seasonal model why exclude dummies in rma model when do you exclude seasonal dummies does seasonality include monthly variables when using seasonal dummies can the t-test be used why exclude seasonal dummies does the t test work for seasonal variation