what is the difference between lag 12 diff and kpss can you differentiate a monthly trend using lag 12 why differentiate between lag 12 and lag 12? when differentiate a time series is stationnarity stationnary is stationnary trend stationary when to use lag 12 differentiation when do you have to differentiate time series to be stationary when do i differentiate my seasonal time series when a time series is stationnary what is the lag? which operator do i use for seasonality and trend test when to differentiate stationnary when is stationnary time series better to differ time series that is stationnary which lag do i use for stationnary time series when is it better to distinguish time series from the kpss how long before differentiation to show if a time series has been stationnary when to apply lag diff operator for stationnarity what is stationnary when can a time series be differentiated