We show that when the money demand function used to estimate the size of the shadow economy includes the lagged dependent variable, the need to assume a known initial condition reappears as it was the case in the early monetary methods.

When a very top group of the income distribution, infinitesimal in numbers, owns a finite share S of total income, the Gini coefficient G can be approximated by G*(1 - S) + S, where G* is the Gini coefficient for the rest of the population. We provide a simple formal proof for this...