The Economist has a very interesting article reporting experiments that show a relationship between smiling in a yearbook photo and divorce later in life.

The Experiment

• The experimenters got hold of about 700 yearbook photos
• The smiles in the photos were then rated
• Smile ratings were then statistically compared with divorce in later life

The Results

• Never divorced subjects had average smile ratings of 5.9
• Divorced subjects had average smile ratings of 5.2 (a statistically significant difference)
• Those who were least smiling were three times more likely to be divorced than those who were most smiling

It seems that statistically significant information can be gleaned from a thin “slice” of information. Smiles really do indicate personality.