Figure 5.
We show the number of confirmed quasars deg−2 (g < 20.5) against the number of stellar sources deg−2 (with g < 21.5). We compare the two algorithms; ugriXDQSO (red circles) and ugriXDQSOW1W2 (blue triangles). By limiting the comparison to brighter quasars we assume the contribution of observational effects is negligible.