Measured experimental decay index, n, vs. numerically calculated predicted critical decay index, ﹩{n}_{\mathrm{cr}}^{}﹩, presented on a log–log plot. The represented shots are limited in edge safety factor, q_a < 0.67. Eruptive shots are represented with red triangles, while noneruptive shots are blue circles. The experimental parameters, z_ap/x_f, ε ≡ a/R, and ℓ_i, of each shot are fit to our numerical model to determine a value of ﹩{n}_{\mathrm{cr}}^{}﹩. The line ﹩n={n}_{\mathrm{cr}}^{}﹩ is also plotted. The model predicts that all shots above this line should be unstable, while the ones below it are stable.