Modifying components of the in-feed system decreased levels of mixing. When all the modifications to the in-feed were implemented, the lowest level of mixing achieved is shown in Fig. 4 with the arrival sequence for 90 markers. This run showed a less-contiguous arrival pattern, suggesting that the pattern is made up of a number of sub-mixing events from the different components in the in-feed system. The overall pattern is, however, adequately described by an exponential distribution (β=297).