parameter is dependent on the study design <em>(number of time-points, sampling rate, time-scale of the function of time under study)</em> and therefore only needs to be selected once per dataset.
</p>
<p>DF Search helps choose an adequate <em>DF</em> to apply across all variables for a given dataset:</p>
<ul>
  <li>A PCA extracts the eigen-trajectories across all variables. The <em>DF</em> that will best fit that subset of eigen-trajectories is expected to be satisfactory for all trajectories in the datase