harbinger vs predictor

harbinger

noun
  • A person or thing that foreshadows or foretells the coming of someone or something. 

verb
  • To announce or precede; to be a harbinger of. 

predictor

noun
  • Something that anticipates, predicts, or foretells. 

  • A predictor variable. 

How often have the words harbinger and predictor occurred in a corpus of books? (source: Google Ngram Viewer )