equation vs identification

equation

noun
  • The act or process of equating two or more things, or the state of those things being equal (that is, identical). 

  • An assertion that two expressions are equal, expressed by writing the two expressions separated by an equal sign; from which one is to determine a particular quantity. 

  • A small correction to observed values to remove the effects of systematic errors in an observation. 

identification

noun
  • The act of identifying (i.e., which one, which thing). 

  • The combination of identifying (which one, which thing) and validating the identity (proving or confirming it); identifying and authenticating viewed as a unitary concept in cognition. 

  • A feeling of support, sympathy, understanding, or belonging towards somebody or something. 

  • A particular instance of identifying something. 

  • A document or documents serving as evidence of a person's identity. 

  • The state of being identified. 

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