SQUEzE trial redshift, z_try, versus true redshift, z_true, for the test sample. Black dots indicate correct classifications. Blue down-pointing triangles, orange up-pointing triangles, and green squares indicate the quasar, galactic, and stellar contaminants respectively. The red solid line shows the perfect classification line and the red stripe show the redshift offset tolerance (∆z = 0.10). Grey squares indicate the area where quasar contaminants are deemed as correct in the relaxed classification scheme (see text for details). From top to bottom and left to right, panels show the data split in four different magnitude bins: 17 < r ≤ 20, 20 < r ≤ 22.5, 22.5 < r ≤ 23.6, and 23.6 < r ≤ 24.3. We note that stellar contaminants (green dots) are always found at z_true = 0.