Judge for yourself: do happiness researchers look happier than economists?

There is a large and growing academic literature on happiness (or subjective wellbeing, as it is more technically called). However, almost all of that literature uses self-reported measures of happiness. I recently read this 2008 paper (open access) by Benno Torgler, Nemanja Antic, and Uwe Dulleck (all QUT) and published in the journal Kyklos, which takes quite a different approach. Torgler et al. showed photographs of top international happiness researchers, economics Nobel Prize winners, and other top economists, to 554 on the streets of Brisbane in 2007, and asked them how happy the people in the photographs were (on a scale of one to four).

Judge for yourself. Here's the photographs they showed (I've blanked out the names, but if you know your famous economists you can probably pick many of them). One of the rows is top happiness researchers, one is economics Nobel Prize winners, and one is other top economists (two of whom have won the Nobel Prize since this research was conducted, and the other two will probably do so within the next few years). Which row is which, and which row is the happiest? (The answers are below, but no peeking until you've made your guesses!).

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Ok, here's the answers. The top row is economics Nobel Prize winners (Edmund Phelps, Daniel Kahneman, Finn Kydland, and Joseph Stiglitz). The second row is other top economists (Paul Krugman, Jean Tirole, Robert Barro, and Paul Romer). Krugman and Tirole have both subsequently won Nobel Prizes. The last row is top happiness researchers (Bruno Frey, Ed Diener, Andrew Oswald, and Richard Easterlin). Which row did you guess was happiest? According to the people that Torgler et al. asked:

We observe a substantial difference between Edmund Phelps, who was perceived to be happiest (with a mean happiness of 3.744) and Andrew Oswald, who was judged least happy (2.045)...

In general, we can see that happiness researchers are perceived to be the most happy. Relative to top economists and Nobel Prize winners, happiness researchers have a higher probability of being adjudged very happy (by 11.1 and 1.8 percentage points, respectively).

So, it appears that happiness researchers are the happiest (at least, as perceived by others based on a single photo taken from their online profile). Seems appropriate. I'm less sure about Torgler et al.'s conclusion:

...the advice for young academics is: if you seek happiness, become a happiness researcher; a Nobel Prize does not make you happier...

Of course, an intrepid researcher could determine whether that last bit is supported by data. Do Krugman and Tirole look happier now in their online profiles than in those earlier photos? You be the judge.