public function get_dirty() {
		$dirty = array();

		foreach ( $this->get_raw_attributes() as $key => $value ) {
			if ( ! array_key_exists( $key, $this->_original ) ) {
				$dirty[ $key ] = $value;
			} elseif ( $value !== $this->_original[ $key ] && ! $this->original_is_numerically_equivalent( $key ) ) {
				$dirty[ $key ] = $value;
			}
		}

		return $dirty;
	}