I am currently teaching a seminar on “positive psychology,” which deals mostly with research on happiness. To date, I have assigned several papers about happiness written by economists, and most of the class, it seems, has found these papers a bit hard to read. Clearly, psychologists and economists approach the same problems quite differently, and here I’d like to offer one example. It involves a fundamental misunderstanding that has been circulating in the media about a recent economics paper reporting that middle-aged people are less happy than younger or older folks.
In the article in question, economists Blanchflower and Oswald reported a “U-shaped” relationship between happiness and age — namely, that middle-aged people are less happy than their younger and older counterparts. (If you think of changes in happiness over time to form the shape of the letter “U,” then younger and older people are at the top two parts of the “U” and the middle-aged are at the trough.) How did these two economists reach this conclusion? Well, if you look at the paper carefully, they actually compared the happiness of the young and old only after statistically controlling for a host of circumstantial factors. In other words, the question they asked is not whether middle-aged people differ in their happiness from others, but whether middle-aged people who are in the same life circumstances as younger and older people differ from others. To be sure, relative to those who are much younger or older, people between ages 40 and 50 are reaching the height of their careers, financially better off, and enjoying their families. Because all of these factors contribute somewhat to happiness, studies that simply compare how happy people are at various ages have found midlife to be one of life’s happier periods. What Blanchflower and Oswald found is that if we assumed that people in their 20s and 70s had the same income, education level, employment, and marital status as the middle-aged, then they’d be happier than those in their 40’s. This might be thought of as the “pure” effect of age. Do you have a hard time grasping what that even means? Then you’ve got company!