Fig. 5

Sink prediction (SourceTracker) in indoor air and unweighted UniFrac phylogenetic distance (ANOSIM R) with indoor air for microbial communities in different source environments. Higher sink prediction values for a source environment indicate a higher proportion of its OTUs in indoor air. R values close to 0 indicate similarity between indoor air microbial communities and the sources; the opposite is true for R values close to 1. The statistical significance (p) of the correlation was determined using Spearman’s rank correlation coefficient (ρ)