Cargo characteristics from modeling operator variance. The distribution of the simulated K_ex values (open symbols) assuming 3 (A,B,D) or 2 (C) cargo classes with K_ex values equaling the mean values obtained from the 3-Gaussian fit shown in Figure 3. The closed symbols represent the 90 K_ex values obtained from our experimental measurements. The Index is simply the ordinal number of the K_ex value. The rate constants and the operator variances used for the analysis are varied in different panels to get a better overlap with the obtained experimental K_ex values. The description of the variable in each panel is as follows: (A) Three cargo classes, K_ex = 0.010, 0.067, and 0.148; σ_op = 0.2. (B) Three cargo classes, K_ex = 0.010, 0.033, and 0.148; σ_op = 0.2. (C) Two cargo classes, K_ex = 0.010 and 0.148; σ_op = 0.2. (D) Three cargo classes, K_ex = 0.010, 0.033, and 0.148; σ_op = 0.1.