Likelihoods for parameters from low-ℓ data. Panels 1–3: one-dimensional posteriors for log [10¹⁰A_s], τ, and A_se^{− 2τ} for the several sub-blocks of the likelihood, for cases 1 (blue), 2 (black), 3 (red), and 4 (green) – see text for definitions; dashed red is the same as case 3 but imposes a sharp prior 10⁹A_se^{− 2τ} = 1.88. Panel 4: two-dimensional posterior for log [10¹⁰A_s] and τ for the same data combinations; shading indicates the 68% and 95% confidence regions.