def add_group_result(result, group: nil)
      data = {result: result}
      if group
        data[:group] = group
      end
      if result.present?
        @group_results << data
      end
    end
def add_group_result(result, group: nil)
      data = {result: result}
      if group
        data[:group] = group
      end
      if result.present?
        @group_results << data
      end
    end
Adds a group result.

 @param [String] result the result of the vote event within a group of voters
 @param [String] group a group of voters