At the extreme ends of the concentration range (for example, fewer than ten copies of target in a well or more than 120,000 copies of target in a well), fewer droplets in a well will lead to slightly larger error bars.

An estimate of par-titioning error can be found based on the analysis of Dube et al.,39 which models the partitioning as a binomial process.

Digital assays have two sources of error: subsampling error and partitioning error

Subsampling error sets the lower detection limit at low concentrations and is independent of the instrument, while partitioning error domi-nates at high concentrations and may depend on the sampling and partitioning instrument