title: Variable importance for support vector machine and naive Bayes classifiers in R
body: <p>I’m working on building predictive classifiers in R on a cancer dataset. 
  I’m using random forest, support vector machine and naive Bayes classifiers. I’m unable to calculate variable importance on SVM and NB models </p>
  
  <p>I end up receiving the following error.</p>
  
  <blockquote>
    <p>Error in UseMethod("varImp") : 
        no applicable method for 'varImp' applied to an object of class "c('svm.formula', 'svm')"</p>
  </blockquote>
  
  <p>I would greatly appreciate it if anyone could help me.</p>