nbest-mix

nbest-mix

NAME

nbest-mix - interpolate N-best posterior probabilities

SYNOPSIS

nbest-mix [-help] option ... weight1 nbest1 weight2 nbest2 ...

DESCRIPTION

nbest-mix reads a number of N-best lists (which must contain identical hypotheses), computes the hypothesis posterior probabilities for each, and computes a new posterior distribution that is a weighted mixture of the input distributions. The hypothesis with the highest combined posterior probability is printed.

The command line arguments form an alternating list of weight values and N-best file names.

OPTIONS

-help
Print option summary.
-debug level
Controls the amount of output (the higher the level, the more).
-write-nbest file
Outputs the N-best list corresponding to the interpolated posterior distribution to a file. This suppresses the printing of the best hyp.
-max-nbest n
Limits the number of hypotheses read from each N-best list to the first n.
-rescore-lmw lmw
Sets the language model weight used in combining the language model log probabilities with acoustic log probabilities (only relevant if separate scores are given in the N-best input).
-rescore-wtw wtw
Sets the word transition weight used to weight the number of words relative to the acoustic log probabilities (only relevant if separate scores are given in the N-best input).
-posterior-scale scale
Divide the total weighted log score by scale when computing normalized posterior probabilities. This controls the peakedness of the posterior distribution. The default value is whatever was chosen for lmw, so that language model scores are scaled to have weight 1, and acoustic scores have weight 1/lmw.

SEE ALSO

nbest-lattice(1).

BUGS

Probably.

AUTHOR

Andreas Stolcke <stolcke@speech.sri.com>.
Copyright 1998 SRI International