just switched LATEX to late and then back again to pdflatex
$\rho$ is now properly defined!

$\rho$ is the ration between the proportion of short hotspots $\gamma$
and the proportion of long hotspots $1-\gamma$ at any one of the four
distributions in Figure 1 (each one corresponding to a prticular data
set). The values of $\gamma$ and the $1-\gamma$ are obtained by
fitting (adjusting) a two component gaussian mixture to the
distribution shown in Figure 1. This is explained at the supplementary
material.
just a notation change $\lambda$ is set to $\gamma$ to be now
consistent with the main text.