Comparison of SQUEzE performance (f₁ score) when using different redshift requirements to define correct classifications. Our fiducial choice is 0.10. The left (right) panel shows the performance for the low (high) redshift quasars. The performance of the fiducial model, with ∆z = 0.10, is marginally worse than the performance with ∆z = 0.15, but the redshift errors are significantly smaller (see Table C.3).