[hammock]

Multiply by .37 to get PERCENTILE change, not percent.

If you were average happiness, and you improve that by 1 stdev, you are now happier than 87% of your peers (when you were at 50%ile before). 0.6 stdev improvement would be vs 72% of your peers.

So to put it colloquially, if you have 7 friends, and you were in the middle of them (4th happiest), by quitting Facebook you are now happier than all but 1 one them.