diff --git a/Project.toml b/Project.toml
index c70244d..218dbba 100644
--- a/Project.toml
+++ b/Project.toml
@@ -1,7 +1,7 @@
 name = "LearnDataFrontEnds"
 uuid = "5cca22a3-9356-470e-ba1b-8268d0135a4b"
 authors = ["Anthony D. Blaom <anthony.blaom@gmail.com>"]
-version = "0.2.0"
+version = "0.2.1"
 
 [deps]
 CategoricalArrays = "324d7699-5711-5eae-9e2f-1d82baa6b597"
diff --git a/src/backends.jl b/src/backends.jl
index 94ec163..03bcc46 100644
--- a/src/backends.jl
+++ b/src/backends.jl
@@ -31,8 +31,8 @@ If [`Sage`](@ref)`(multitarget=..., code_type=...)` has been implemented, then
 `observations.target` has an integer element type controlled by `code_type`, and we
 additionally have:
 
-- `observations.levels`: A categorical vector of the ordered target levels, as actually
-  seen in the user-supplied target. The corresponding integer codes will be
+- `observations.levels_seen`: A categorical vector of the ordered target levels, as
+  actually seen in the user-supplied target. The corresponding integer codes will be
   `sort(unique(observations.target))`. To get the full pool of levels, apply
   `CategoricalArrays.levels` to `observations.levels_seen`; see the example below.