are dummy interactions always stationary which is non-stationary interaction why is dummy interaction variables always nonstationary why is an interaction variable non stationary when a variable is always non stationary, what is the smallest point of the model? which interaction variable is never stationary can we include a dummy interaction into a time series model if they're always non stable? are dummy variables always non-stationary why dummy interactions aren't stationary in the rpg why are dummy interaction terms always nonstationary? which interaction variable is always nonstationary? how are dummy variables nonstationary why are dummy interactions stationary are dummy variables always non stationary what is the interaction variable for a time series is dummy interaction variable stationary are interactions always non-stationary are dummy variable always stationary are dummy interaction variables always stationary if a dummy variable is dummy a variable is