Sorry I don’t have a lot of info on hand about the way that the scoring works — I made a decision to pass the score along via the API because it was available as data and it seemed like overreaching to decide not to pass it back through the callback, but based on my discussions with the CMU Sphinx folks it doesn’t provide a lot of viable info for language models of the size that are appropriate for iPhone apps so I haven’t done a lot of investigation of its intricacies myself. My general advice is that you should base any logic that makes use of the score on data that emerges from well-organized and diverse tests rather than an interpretation of the scoring method.