Bell and Blanchflower (2018)
Bell, David N.F., and David G. Blanchflower. "The Well-being of the Overemployed and the Underemployed and the Rise in Depression in the UK." NBER Working Paper No. 24840, July 2018.
From the authors' abstract: "The underemployed have higher levels of well-being than the unemployed and disabled but lower levels than any other group of workers, full or part-time. The more that actual hours differ from preferred hours the lower is a worker's well-being. This is true for those who say they want more hours (the underemployed) and those who say they want less (the over employed).
"We find strong evidence of a rise in depression and anxiety (negative affect) in the years since the onset of austerity in 2010 that is not matched by declines in happiness measures (positive affect). The fear of unemployment obtained from monthly surveys from the EU has also been on the rise since 2015. We find evidence of an especially large rise in anxiety and depression among workers in general and the underemployed in particular. The underemployed don't want to be underemployed."
LK comment: This is particularly pertinent given the rise of casual labor / gig economy business models. One potential downside of these is that workers may be less productive than expected if they are, on average, underemployed relative to their preferences, potentially impacting financial results.