Comparison of z_FIR with spectroscopic redshifts. Circles indicate AzTEC/C sources, squares represent SPT sources (Weiß et al. 2013), and asterisks represent galaxies from other surveys (see Table 1). The star represents Vd-17871 (also included in our training set). The error bars show the error due to the combined uncertainty of λ_peak and the linear relation between λ_peak and z_spec multiplied by 2.5 times such that 68% of the sample has consistent values of z_FIR and z_spec.