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For the three amount ratios: visit length (presses per visit) following the larger amount as a function of the comparable visit length following the smaller amount, replotted from Figure 7. The sequences of food deliveries are mirror images—for example, 4-4-4-4 versus 1-1-1-1 or 1-1-1-4 versus 4-4-4-1. Triangles indicate continuations and squares discontinuations.
