Markov chain Monte Carlo analysis regarding the constraining power of B/R (blue) and SED (red) of Warhol on the parameter space, given that we assume there is only one single burst of star formation at age t with metallicity Z_★ and dust extinction A_V. Since we only care about the inference of these three parameters, all the SED templates generated by SPISEA are pre-normalized to best fit the observed SED of Warhol. The contour levels correspond to 1 − 4σ level confidences. Histograms/contours in solid lines represent the case for a Kroupa IMF, where those in dotted lines (with a slight color tweak to improve visibility) represent the case for a top-heavy IMF. There is no significant difference in preference for star formation parameters constrained by either B/R or SED when a different IMF is adopted.