As expected, the homopolymer length was the main contributor to the mean of the flow-value distribution ( Table 3 ). Contrary to expectation, the coefficient for homopolymer length was not 1, but 0.975. Thus, with each additional base in a homopolymer, we see a decrease in the mean flow value of 0.025 (i.e. 0.975 main effect for a homopolymer of length 1, 1.95 for length 2 and so on). This shift downwards drives the increasing ‘gap’ between the deletion-rate versus the insertion-rate with increasing hompolymer length, consistent with our observation that deletions are the dominant error-type on longer homopolymers (Figure S8).
