missingness vs vacuity

missingness

noun
  • Absence. 

  • The manner in which data are missing from a sample of a population. 

  • Missing data; omission. 

vacuity

noun
  • Emptiness. 

  • Idleness; listlessness. 

  • Physical emptiness, an absence of matter; vacuum. 

  • An empty or inane remark or thing. 

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