Left-hand panel: Distribution of the estimated probability that an individual clump location is inaccurate (|$p^{\sigma }_{l}$|) for clumps identified using 20 annotations per subject (i.e. using |$\tilde{Z}_{20}$|). The distribution is concentrated close to zero with all clumps having |$p^{\sigma }_{l}\lesssim 0.3$|. The inset shows the distribution in for |$p^{\sigma }_{l} < 0.01$|. Right-hand panel: Distributions of |$p^{\sigma }_{l}$| corresponding to n between 3 and 20 volunteer annotations per subject. The distribution medians decrease monotonically from ≈0.05 for n = 3 to ≈4 × 10−4 for n = 20, while the distribution interquartile ranges become wider as more volunteers annotate each subject. Note that the colour scale shows the number density of clumps to account for the fact that the two-dimensional histogram bins cover different areas.
