diff --git a/Project.toml b/Project.toml
index a4e3f03..057f034 100644
--- a/Project.toml
+++ b/Project.toml
@@ -1,7 +1,7 @@
 name = "StatisticalTraits"
 uuid = "64bff920-2084-43da-a3e6-9bb72801c0c9"
 authors = ["Anthony D. Blaom <anthony.blaom@gmail.com>"]
-version = "3.0.0"
+version = "3.0.1"
 
 [deps]
 ScientificTypesBase = "30f210dd-8aff-4c5f-94ba-8e64358c1161"
diff --git a/src/StatisticalTraits.jl b/src/StatisticalTraits.jl
index 6429565..e8cd975 100644
--- a/src/StatisticalTraits.jl
+++ b/src/StatisticalTraits.jl
@@ -138,7 +138,7 @@ snakecase(s::Symbol) = Symbol(snakecase(string(s)))
 input_scitype(::Type)          = Unknown
 output_scitype(::Type)         = Unknown
 target_scitype(::Type)         = Unknown
-fit_data_scitype(::Type)       = Unknown
+fit_data_scitype(::Type)       = Tuple{Unknown}
 predict_scitype(::Type)        = Unknown
 transform_scitype(::Type)      = Unknown
 inverse_transform_scitype(::Type)  = Unknown