FIGURE 4.

Each model (A) is characterized by a set of two correlations (B). Note that these defining correlations require 1 additional parameter S_b for the sHC model, 1 additional parameter s_i for the RDA and the IA models, whereas the IDA model requires 2 additional parameters, s_i and S_b. (C) As a result, the covariance matrix for the I-value analysis of these models, according to Witz et al. (2019), would be 4x4 for the sHC, IA and RDA models and 5x5 for the IDA model. Therefore, the I-values of these models cannot be meaningfully compared.