policymakers demonstrate

556 Alain Trannoy
returns of college graduates, while the returns of other qualifications had suffered
from different causes (adverse technical progress, trade liberalization, and
immigration of low-skilled workers). Not all economists agree with Piketty’s
demonstration and this issue should remain on the research agenda.
Second, the increasing gulf between CEOs pay in large companies and the
earnings of other employees remains puzzling. Some economists (Gabaix and
Landier, 2008 and Gabaix et al., 2014) argue that it simply reflects the increasing
size of the companies and the increasing risk associated with bad decisions
by managers. Other economists such as Atkinson (2015) argue that it comes
from the change in social norms. Clearly more research in this direction is
needed.
Third, the digitalization of many services to consumer (sometimes depicted
as ‘uberization’) raises new challenges. A growing part of the labour force
may become self-employed, and their social protection may be reduced with
respect to a world of homogeneous employees. The empirical evidence here is
not straightforward since the evolution of the labour market points in the US and
in the UK towards two divergent directions. There is the fear that this disintermediation
reorients market forces in a way that is more inequality prone. This
research programme can be viewed as an outgrowing of the linkage between
technical progress and inequality.
Fourth, the happiness literature, and more specifically John Layard, draws
attention to the fact that most of the worst unhappiness is caused by mental
disorders, especially depression and schizophrenia. According to John Layard
‘Roughly 25 per cent of us experience serious mental illness during our lives,
and about 15 per cent experience major depression.’
More importantly, there is much evidence on the correlation between different
dimensions of deprivation during younger age and outcomes later in life,
and that social deprivation correlates with both personality features and with
mental health later in life. Here, I see an important missing relationship between
equality of opportunity and mental disorders that opens possible new vistas for
research.
In particular, for people of working age, mental or emotional health problems
may lead an individual to leave his job, to be fired or to make him difficult
to get out of unemployment. His saving or borrowing decisions may be inappropriate
and as long as he has to take care of children, this can be detrimental
to their development. Addiction can go along with mental health problems and
affected people can even plunge into extreme poverty and become homeless.
As long as a person can switch from an economic and social status to a lower
status because of mental health problems, or involves someone else to follow a
downward path (mainly children), mental health problems demand some action
from the public authorities. The gist of the argument is about the bad dynamics
with potential externalities entailed by mental health problems. Social policy