big name vs unknown

big name

noun
  • A prominent individual, especially one who is favorably regarded. 

  • A widely-known reputation, especially one that is favorable. 

unknown

noun
  • A variable (usually x, y or z) whose value is to be found. 

  • A person of no identity; a nonentity 

  • Any thing, place, or situation about which nothing is known; an unknown fact or piece of information. 

adj
  • Not known; unidentified; not well known. 

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