how to do stationarity test in time series how do you test stationarity in r why does pfaff test for stationarity how to test for a stationary trend what is df and stationarity tests how to find trend in r why is adf test called the adf test what is stationary testing? what test will show the trend in linear regression if the null hypothesis is rejected? why a stationary test is required what is the statistical test pfaff used for when the trend is not positive, the underlying unit root is when to use stationary tests what test should be used for a stationary time series when a model is stationary, what type of test do you use for this what is the normal test for ADF how to find a stationary model in r why is the adf test necessary which statistic is a stationary test what is pfaff's stationarity test