  The `paradox of progress' is an empirical regularity that associates more
education with larger income inequality. Two driving and competing factors
behind this phenomenon are the convexity of the `Mincer equation' (that links
wages and education) and the heterogeneity in its returns, as captured by
quantile regressions. We propose a joint least-squares and quantile regression
statistical framework to derive a decomposition in order to evaluate the
relative contribution of each explanation. The estimators are based on the
`functional derivative' approach. We apply the proposed decomposition strategy
to the case of Argentina 1992 to 2015.
