Fig. 6From: Bacterial community assemblages in classroom floor dust of 50 public schools in a large city: characterization using 16S rRNA sequences and associations with environmental factorsUnconstrained nonmetric multidimensional scaling (NMDS) for 50 schools (denoted by filled diamonds) grouped into quartiles (by different colors) in each environmental variable. Ellipses were constructed with a 95% confidence interval using standard error in chi-square distribution with two degrees of freedomBack to article page