> Laotians smile the 3rd most, but are also among the angriest

From "Be Careful Where You Smile: Culture Shapes Judgments of Intelligence and Honesty of Smiling Individuals"

  Although numerous studies confirm that positive perceptions of smiling 
  individuals seem to be universal, anecdotal evidence suggests that in some 
  cultures the opposite may be true. For example, a well-known Russian proverb 
  says ‘Улыбкa, бeз пpичины - пpизнaк дypaчины’ (smiling with no reason is a 
  sign of stupidity). The Norwegian government humorously explains nuances of 
  Norwegian culture by indicating that when a stranger on the street smiles at 
  Norwegians, they may assume that the stranger is insane