Fig 9. Poisson Confidence intervals for 48 independent dilutions of a rare target.

The bottom axis shows the number of copies in the reaction, the top axis shows the number of droplets analysed (as indicated by the green bar-plots). The vertical line indicates the median estimate, confidence intervals that contain this value are coloured black, confidence intervals that do not contain this value are represented as empty boxes. Panels A through D show the decrease in confidence width as a consequence of merging the reactions, the respective CI coverage factors for the panels are: 93.75, 81.25, 75, and 70.83 percent.