The problem, according to the book, of the current measures of happiness used in happiness studies is that the values so obtained are incommensurable over time and people. The following thought examples illustrates the problem.
Suppose a researcher randomly selects Joe and asks him to rate the current tidiness of his home on the scale of 1-10, with 1 representing the least tidy home he can imagine and 10 representing the tidiest. Joe says ‘7’. Later the researcher randomly selects Betsy and asks her to do the same with respect to her home. She also answers a ‘7.’ Should we conclude that both their homes are equally tidy?
Of course not. Joe’s 7 is not the same as Betsy’s 7, because the two people are likely to have different conceptions of what constitutes the “least tidy” and “tidiest.” What if the the researcher repeated the exercise again 10 years later and Joe once again rated his level of tidiness ‘7.’ Would we take that to be an indication that there has been no improvement in the state of Joe’s home? No, because it is more likely that his standards of tidiness have changed (for the better, we hope), and his ‘7’ now represents a different level of tidiness than 10 years before.
We would therefore be justified in believing that such self-reported scores are not comparable across people and across time. We would likely be amused at any study that compared the average value of such self-ratings in our city to the average value in other cities around the world and declared which city had the tidiest homes. Ditto for a study that used such self- ratings to report if we had gotten tidier over time. But we would certainly not consider these studies as providing a strong argument for radically restructuring our health and safety regulations, infrastructure, and culture with the aim of getting ourselves to be tidier.
Substitute “happiness” for “tidiness” in the above scenario and you will see one of the problems, as described in this book, with the happiness research and the policy implications drawn from them. Simply put, the happiness are not commensurable across time and people.
Before discussing such problems, however, the authors review extensively the studies of the various correlates of happiness–as measured by people’s self-reported ratings. We learn from their review of the literature that people being employed, married, socially connected, and enjoying a good provision of public services is correlated with high levels of self reported happiness.
The authors also argue against the policy implications that several researchers have drawn from the Easterlin Paradox–the finding that higher absolute income is not correlated with higher self-reported happiness. Some researchers and policy advocates have taken this to make a case for strong governmental curbs on our striving for increased income in order to divert our energies towards activities that studies have shown would increase happiness. But because of the problem of incommensurability of self-ratings, the authors are loath to draw such radical policy implications from studies that use self-ratings.
They point our that the paradox has also not held up in the latest studies. Researchers nowadays distinguish between two different conceptions of happiness (i) the feeling of pleasure or joy, usually in response to something that has happened in the moment (ii) the feeling of satisfaction when one reflects back on their life has a whole. It turns out that a higher income beyond a certain level seems to not provide more in-the-moment joyful experiences, but it continues to improve how overall satisfying people find their lives to be. Thus any governmental attempt to increase our happiness by curbing our economic aspirations would be misguided.
Overall, I would say this a great book for those who want a survey of the latest research in happiness economics.