Contour plots of σ / μ in three hyperplanes: (a) for ( v = v
, u , ϵ ), (b) for ( v , u = u
, ϵ ), and (c) for ( v , u , ϵ = ϵ
). The position of the resistor model operating point is marked by the white circle. Contour lines are labelled by their respective σ/μ values (square boxes). Lighter (darker) regions indicate where noise does (does not) dominate the dynamics.