Here the BBP threshold is .0025. Below the threshold nothing interesting is found by the TW unsupervised statistic. Above the threshold, the TW statistic is usually highly significant, and the ANOVA analyses show that the true structure has become apparent. At the threshold we sometimes have recovered significant structure, but it will be hard (usually impossible) to tell if the structure is real or a statistical artifact. Below the threshold, the structure is too weak to be useful. In these runs, at the critical threshold, the eigenanalysis slightly outperformed STRUCTURE. We have not carefully investigated whether we could obtain better results by varying the STRUCTURE parameters.
