Fig. 2

Masked tip date inference from genomes (left) and GP sequences (right). Inferred collection dates in the masked set based on genomes (red, left) and GP sequences (blue, right). Each vertical line corresponds to the 95% highest posterior density for the inferred tip date (y-axis) coloured red (genome) or blue (GP) if it falls within the true collection date (x-axis) and black otherwise. Dashed diagonal line indicates the 1-to-1 line. A histogram of signed residual errors between mean posterior date estimate and true date for each masked tip is shown in the second row with the black hatch indicating the mean. A histogram of absolute residual errors (accuracy) between mean posterior date estimate and true date for each masked tip is shown in the third row with the black hatch indicating the mean and the higher black hatch topped with a circle corresponding to a theoretical expectation based on Eq 2. Fourth row shows the histogram of confidence interval widths for date estimates (precision)