(a) Values of ﹩\chi ^{2}_{\mathrm{MS}\,}﹩ computed for the SFR const‐const model and with IMF x = 2.35 to test the simulated sample (produced with constant SFR and x = 2.35). T_b varies between T_i and T_f, spaced by 1 Gyr. Each line corresponds to a different value of I_b. Squares indicate models whose probability P from the K‐S test is greater than 0.1. (b) Same as (a) but for ﹩\chi ^{2}_{\mathrm{red}\,}﹩. Solid triangles indicate that condition Rb is satisfied; open triangles correspond to models that satisfy condition Rc.