title: Intervention Detection in Python Time Series (Pulse, Trend, Shift)
body: <p>I'm trying to filter out outliers in my time series data that exhibit unexplained spikes (pulses), trends over time, or level shifts. The purpose is to get data that is stable in the pre and post periods, so that the effects in the middle can be estimated.</p>
  
  <p>What kind of tools are available for ARIMA modeling of intervention detection? I've been surprised by how little I could find so far.</p>