title: How to compute machine learning training computation time and what are reference values?
body: <p>in many forums and documents on the internet we hear about "short" and "long" learning and prediction computation time for machine learning algorithms. For example the Decision Tree Algorithm has a short computation time as compared to Neural Networks. But what it is never mentioned is what is "short" and what is "long".</p>
  
  <p>Could you please clarify which unit you would use to measure computation time? Maybe "seconds per sample"? And what are reference values, so that I can predict if it takes 1h, 1day or 1Week?</p>
  
  <p>Thanks
  Kind regards
  G</p>