Orange circles indicate ATLASGAL clumps containing HII regions and the cyan circles represent clumps without the presenceof HII regions, which consist of IR bright non-HII and dark non-HII regions. The black dashed lines indicate equality. The error bars are obtained from Gaussian or HFS fits. The red and blue ellipses are covariance error ellipses with 1σ (inner ellipse) and 2σ (outer ellipse) for the two groups.