Happyism: The Creepy New Economics of Pleasure. Economist Dierdre McCloskey, in the New Republic, digs into the mathematical underpinnings of the scientific study of happiness. Executive summary: she doesn't like what she finds.
"We infer that beyond about $75,000/y, there is no improvement whatever in any of the three measures of emotional well-being." Two social scientists at Princeton, Angus Deaton and Nobelist Daniel Kahneman, have a new paper in PNAS about money and the determinants of happiness. Increased income above $75,000 is not associated with higher subjective happiness, though it is associated with superior scores on measures of overall life satisfaction. Other tidbits: "Religion has a substantial influence on improving positive affect and reducing reports of stress, but no effect on reducing sadness or worry... The presence of children at home is associated with significant increases in stress, sadness, and worry."