for the birds vs plausible

for the birds

adj
  • Worthless; useless; pointless; not deserving serious consideration. 

plausible

adj
  • Obtaining approbation; specifically pleasing; apparently right; specious. 

  • Seemingly or apparently valid, likely, or acceptable; conceivably true or likely. 

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