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Thursday, October 20, 2022

The Age Trajectory of Happiness

Kratz, F., & Brüderl, J. (2021, April 18).


A large interdisciplinary literature on the relationship between age and subjective well-being (happiness) has produced very mixed evidence. Virtually every conceivable age-happiness trajectory has been supported by empirical evidence and theoretical arguments. Sceptics may conclude that the social science of happiness can only produce arbitrary results. In this paper we argue that this conclusion is premature. Instead, the methodological toolbox that has been developed by the modern literature on causal inference gives scholars everything they need to arrive at valid conclusions: the causal inference toolbox only must be applied by happiness researchers. We identify four potential sources of bias that may distort the assessment of the age-happiness relationship. By causal reasoning we derive a model specification that avoids these  biases.  For  an  empirical  illustration,  we  use  the  longest  running  panel  study  with information on happiness, the German Socio-Economic Panel (1984-2017; N persons=70,922; N person-years =565,703). With these data we demonstrate the relevance of the four biases and how combinations of different biases can reproduce almost any finding from the literature. Most biases tend to produce a spuriously U-shaped age trajectory, the most prominent finding from the literature. In contrast, with our specification we find a (nearly monotonic) declining age-happiness trajectory.

Summary and Conclusions

How aging affects happiness is an important research question for the social and behavioral sciences. Our literature review demonstrates that many conflicting age trajectories have been reported in the literature. As this state of research is quite unsettling for the science of happiness, we  discuss—informed  by  recent  advances  in  the  methodology  of  causal  analysis—model specifications used by researchers in this field. Altogether, we identify four main biases that may distort the age trajectory of happiness. By using the German SOEP data, we show that distortions may be huge producing even qualitatively different conclusions. We demonstrate that by using different combinations of mis-specifications it is possible to generate (almost) every trajectory that has been reported in the literature. With a model specification that avoids these four biases, we find an age-happiness trajectory that declines slowly over adulthood (altogether about half a scale point). The decline comes to a halt and we observe even a small increase (about one tenth of a scale point) during the golden ages. Afterwards, in old age a very steep decline in happiness sets in.