diff --git a/app/logical/tag_category.rb b/app/logical/tag_category.rb
index c36d15c62..61825010c 100644
--- a/app/logical/tag_category.rb
+++ b/app/logical/tag_category.rb
@@ -46,7 +46,7 @@ class TagCategory
     end
 
     def category_ids
-      @@categories ||= canonical_mapping.values
+      @@category_ids ||= canonical_mapping.values
     end
 
     def short_name_list