(A,B) Mean height 〈y〉 of the agents for different sizes up to N = 70 (Nh = 64), for 10 different agents and 101 values of β. (C,D) Susceptibility of the agent’s behaviour, computed as \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${\chi }_{y}(\beta )=\beta \frac{\partial \langle y\rangle }{\partial \beta }$$\end{document}χy(β)=β∂〈y〉∂β, where 〈y〉 is estimated using B-splines. Maximum and minimum values are shown by the grey area. The figures suggest that in both the Mountain Car (left) and Acrobot (right) embodiments the behaviour of the agent presents a sharp transition around β = 1.