Top panel: Marginalized posterior distributions of f_NL for five different observables: μ₁ (purple), μ₂ (green), μ₃ (yellow), [μ₁, μ₂] (pink), and [μ₁, μ₂, μ₃] (our full model, cyan; see Eq. (16) and Fig. 6). Each observation vector is constructed and sampled independently using the f_NL = 12 test simulations. Dashed lines indicate the median value of the MCMC posterior for each case, with corresponding uncertainties (16th and 84th percentiles) annotated in the upper left. Bottom panel: 1σ uncertainty on f_NL as function of maximum scale, s_max, used in the observation vector. Colors correspond to those in the top panel. Each point represents an independent sampling using bins up to that s_max. The dashed vertical gray line marks the s_max adopted for the main analysis.