title: Merge attributes in different way in weka
body: <p>I'm using Weka to pre-process dataset. The problem is that I have an attribute '<strong>medical speciality</strong>' that contains a lot of labels more than 70 so by exploding it (change it from nominal to binary), I got 70 more attributes in the data set. So I found a way to minimize this number as much as possible: </p>
  
  <p>here is an example of the values of labels to understand the idea:</p>
  
  <p><strong>*Pediatrics</strong></p>
  
  <p><strong>*Pediatrics-Endocrnology</strong></p>
  
  <p><strong>*Endocrinology</strong></p>
  
  <p>So I need to keep only <strong>Pediatrics</strong> and <strong>Endocrinology</strong> as attributes and for the instances in <strong>Pediatrics-Endocrnology</strong> they will have a 1 in <strong>Pediatrics</strong> and 1 in <strong>Endocrinology</strong>.</p>
  
  <p>How can I do that with weka ?? Any suggestion ??</p>