Training sets used for the naïve Bayesian classification of bacterial 16S rRNA gene sequences.

aExcept for the ‘RDP TS6’ training set, which always trains on the full sequence, numbers are only for the testing of 100 nt single-reads from the V4 region. For the three other training sets, which train only on the region to be classified, the number of sequences reflects both the number of sequences covering this region (all three training sets) and its degree of redundancy (‘unfiltered RDP’ and ‘filtered NCBI’).
bThe numbers are for the ‘original non-redundant training set’ (see Methods section ‘Leave k out classification testing’); numbers for each leave-k-out iteration may vary slightly.