23. A speech processing arrangement according to claim 16 , in which selected positions in the N-best list are reserved for recognition hypotheses of one or more selected rescoring categories.
16. A speech recognition processing arrangement comprising: an automatic speech recognition engine having: means for producing an N-best list of recognition hypotheses corresponding to a spoken input; and means for rescoring the hypotheses to produce a rescored N-best list output; wherein the rescoring uses a plurality of rescoring categories based on position in the rescored N-best list such that some positions in the rescored N-best list are rescored based on a first combination of rescoring categories and other positions in the rescored N-best list are rescored based on a second combination of rescoring categories.