diff --git a/lib/searchkick/query.rb b/lib/searchkick/query.rb
index 8cc6e52..1112915 100644
--- a/lib/searchkick/query.rb
+++ b/lib/searchkick/query.rb
@@ -583,7 +583,8 @@ module Searchkick
         unless attributes[:origin]
           raise ArgumentError, "boost_by_distance requires :origin"
         end
-        function_params = attributes.select { |k, _| [:origin, :scale, :offset, :decay].include?(k) }
+
+        function_params = attributes.except(:factor, :function)
         function_params[:origin] = location_value(function_params[:origin])
         custom_filters << {
           weight: attributes[:factor] || 1,
--
libgit2 0.21.0