FIGURE 5.

Hierarchical cumulative probability model predicts previously unseen bacteria with varying performance. Leave-one-group-out cross-validation was used to estimate predictive performance of hierarchical CPM for previously unseen bacteria. The predictive errors are constrained below one order of magnitude for most bacteria, except for Bacillus cereus–which reached errors of almost two orders of magnitude (lower panel). The dashed gray line indicates a value of 1, representing one order of magnitude in the context of MALR. The model fails to classify abundance values of Bacillus cereus (upper panel), although ordinal association (D_xy) remains above 0.6. Most absolute errors represent no more than two times the observed abundances in a context of logarithmic differences–except for B. cereus and (slightly) E. faecalis using CHP. For visualization, we truncated the y-axis of the lower panel at the value of 10 and indicated higher values with numeric labels.