mock up vs sketch out

mock up

verb
  • To create a model or demonstration; to create a preliminary version or sample. 

sketch out

verb
  • To creep out; to give a creepy or sketchy feeling to. 

  • Used other than figuratively or idiomatically: see sketch, out. 

How often have the words mock up and sketch out occurred in a corpus of books? (source: Google Ngram Viewer )