Coanalytic set

In the mathematical discipline of descriptive set theory, a coanalytic set is a set (typically a set of real numbers or more generally a subset of a Polish space) that is the complement of an analytic set (Kechris 1994:87). Coanalytic sets are also referred to as ${\mathrm{\Pi }}_1^1$ sets (see projective hierarchy).

References

• Template:Citation

Template:Settheory-stub