The 20 smilers are British, so if there is indeed is such thing as “English Reserve” it may have affected my judgement, in comparison to here, where, if a Southerner smiles ay you, you stays smiled-at.
The results page states that surpringly few people can accurately read smiles, but didn’t show how my results compare.
I got 17 our of 20 correct
Two who were genuine I saw as fake
One faker got by me
Link to the test: http://www.bbc.co.uk/science/humanbody/mind/surveys/smiles/