mistake vs strictness

mistake

verb
  • To understand wrongly, taking one thing or person for another. 

noun
  • An error; a blunder. 

  • A pitch which was intended to be pitched in a hard-to-hit location, but instead ends up in an easy-to-hit place. 

strictness

noun
  • The state or quality of being strict. 

  • The result or product of being strict. 

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