authorization vs certification

authorization

noun
  • An act of authorizing. 

  • (A document giving) formal sanction, permission or warrant. 

  • Permission. 

  • Permission, possibly limited, to spend funds for a specific budgetary purpose. 

certification

noun
  • The act of certifying. 

  • The granting of a certificate. 

  • A professional qualification that certifies a person's ability. 

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