title: Variable encoding in R- Survey - Ranking nominal variables
body: <p>Despite my research I don't understand how to define (and so code) some results of my survey.</p>
  
  <p>I have questions that asked respondant to rank the modalities, ex : Classify the following means of transport based on your preferences : car, train, plane.
  And, others that ased to rank on a scale their perception regarding a product, ex : On a scale from one to ten, evaluate something. </p>
  
  <p>I think that in the later case, Likert scale is appropriated (is there other method ?). However I've not idea of what I've to use for the first one.</p>
  
  <p>Any idea please ?</p>
  
  <p>Thank you !</p>