Proportion of unstable sequences, proportion of unstable OTUs, and MCC value of each method. (a) Proportion of unstable sequences as created by method. Unstable sequences are defined as sequences that are clustered to one centroid in the 60% subsample but clustered to a different centroid in the 100% (full) dataset. (b) Proportion of unstable OTUs as created by method and by frequency of cluster centroids (the values for closed-reference and dereplication are zero and are thus not included in this figure). If an OTU was identical in the 60% and 100% datasets (not including sequences that are not present in the 60% subsample), it is defined as stable. (c) MCC value of each method. Higher values correspond to greater stability.