Figure 5: The logarithms of ratios of slopes of functions characterizing resistance to change in two-component multiple VI VI schedules that differ in reinforcer rate or amount are related to the logarithm of the reinforcer ratio. The data points are averages across subjects for separate experimental conditions and methods for evaluating resistance to change, coded as follows: Nevin et al. (1983) 1: timeout food; 2: Extinction. Nevin et al. (1990) 3: Experiment 1, prefeeding; 4: Experiment 1, extinction; 5: Experiment 2, prefeeding; 6: Experiment 2, extinction. Nevin (1992a) 7: Prefeeding; 8: Extinction. Points numbered 9 represent single conditions from Shettleworth and Nevin (1965), extinction; Nevin (1974) Experiment 1, timeout food; Nevin (1974) Experiment 2, extinction; Nevin (1974) Experiment 3, timeout food; and Nevin (1988), extinction. From Nevin (1992b).