Figure 1. Best-performing model fits of the P₁/P₂ ratio as V₃ is varied.

Left, the original Louie et al. dataset; right, the Gluth et al. replication. IIA is represented by the dashed line. These fits are generated for the average V₁ and V₂ observed in each sample. In the Louie et al. dataset, Divisive Normalization with the MVN error captures a u-shaped non-monotonic pattern in the P₁/P₂ ratio. In the Gluth et al. dataset, Divisive Normalization with the Gumbel error captures a decreasing pattern. Overall, both datasets show evidence for normalization but differ in the specific pattern of context-dependence, suggesting subtle differences in the choice data.