112 lines
4.3 KiB
HTML
112 lines
4.3 KiB
HTML
<! $Id: nbest-mix.1,v 1.8 2019/09/09 22:35:37 stolcke Exp $>
|
|
<HTML>
|
|
<HEADER>
|
|
<TITLE>nbest-mix</TITLE>
|
|
<BODY>
|
|
<H1>nbest-mix</H1>
|
|
<H2> NAME </H2>
|
|
nbest-mix - interpolate N-best posterior probabilities
|
|
<H2> SYNOPSIS </H2>
|
|
<B>nbest-mix</B> [ <B>-help</B> ] <I>option</I> ... <I> weight1 nbest1 weight2 nbest2</I> ...
|
|
</PRE>
|
|
<H2> DESCRIPTION </H2>
|
|
<B> nbest-mix </B>
|
|
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.
|
|
<P>
|
|
The command line arguments form an alternating list of
|
|
weight values and N-best file names.
|
|
<H2> OPTIONS </H2>
|
|
<P>
|
|
Each filename argument can be an ASCII file, or a
|
|
compressed file (name ending in .Z or .gz), or ``-'' to indicate
|
|
stdin/stdout.
|
|
<DL>
|
|
<DT><B> -help </B>
|
|
<DD>
|
|
Print option summary.
|
|
<DT><B> -version </B>
|
|
<DD>
|
|
Print version information.
|
|
<DT><B>-debug</B><I> level</I><B></B><I></I><B></B><I></I><B></B>
|
|
<DD>
|
|
Controls the amount of output (the higher the
|
|
<I>level</I>,<I></I><I></I><I></I>
|
|
the more).
|
|
<DT><B>-write-nbest</B><I> file</I><B></B><I></I><B></B><I></I><B></B>
|
|
<DD>
|
|
Output N-best lists containing scores that correspond to the log of
|
|
the combined posteriors of the input hypotheses.
|
|
The log posterior is assigned as the acoustic score and other scores
|
|
are set to zero.
|
|
This also suppresses the printing of the best hyp.
|
|
<DT><B>-max-nbest</B><I> n</I><B></B><I></I><B></B><I></I><B></B>
|
|
<DD>
|
|
Limits the number of hypotheses read from each N-best list to the first
|
|
<I>n</I>.<I></I><I></I><I></I>
|
|
<DT><B>-rescore-lmw</B><I> lmw</I><B></B><I></I><B></B><I></I><B></B>
|
|
<DD>
|
|
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).
|
|
<DT><B>-rescore-wtw</B><I> wtw</I><B></B><I></I><B></B><I></I><B></B>
|
|
<DD>
|
|
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).
|
|
<DT><B>-posterior-scale</B><I> scale</I><B></B><I></I><B></B><I></I><B></B>
|
|
<DD>
|
|
Divide the total weighted log score by
|
|
<I> scale </I>
|
|
when computing normalized posterior probabilities.
|
|
This controls the peakedness of the posterior distribution.
|
|
The default value is whatever was chosen for
|
|
<I>lmw</I>,<I></I><I></I><I></I>
|
|
so that language model scores are scaled to have weight 1,
|
|
and acoustic scores have weight 1/<I>lmw</I>.
|
|
<DT><B> -set-lm-scores </B>
|
|
<DD>
|
|
In conjunction with
|
|
<B>-write-nbest</B>,<B></B><B></B><B></B>
|
|
output N-best lists that preserve the acoustic scores and word counts
|
|
of the (first of the) input N-best lists, and encodes the combined
|
|
log posteriors via the LM scores.
|
|
The LM scores in the output are calculated so that, when combined with
|
|
the acoustic scores and insertion penalties (using the given LM weight
|
|
and posterior scaling), the result is the weighted, combined posteriors based
|
|
on all input N-best scores.
|
|
This option is useful if input N-best lists were created by rescoring with
|
|
different language models, and the output N-best lists are to be combined
|
|
with other scores or if the score weighting is to be optimized with
|
|
<A HREF="nbest-optimize.1.html">nbest-optimize(1)</A>.
|
|
<DT><B> -set-am-scores </B>
|
|
<DD>
|
|
Analogous to
|
|
<B>-set-lm-scores</B>,<B></B><B></B><B></B>
|
|
except that the acoustic scores are modified to reflect combined log posterior
|
|
probabiltities, and other scores are preserved.
|
|
This option is useful if input N-best lists were created by rescoring with
|
|
different acoustic models.
|
|
</DD>
|
|
</DL>
|
|
<H2> SEE ALSO </H2>
|
|
<A HREF="nbest-lattice.1.html">nbest-lattice(1)</A>, <A HREF="nbest-scripts.1.html">nbest-scripts(1)</A>, <A HREF="nbest-optimize.1.html">nbest-optimize(1)</A>.
|
|
<BR>
|
|
A. Stolcke, K. Ries, N. Coccaro, E. Shriberg, R. Bates, D. Jurafsky, P. Taylor,
|
|
R. Martin, C. Van Ess-Dykema, & M. Meteer,
|
|
``Dialogue Act Modeling for Automatic Tagging and Recognition of Conversational
|
|
Speech,''
|
|
<I>Computational Linguistics</I> 26(3), 339-373, 2000.
|
|
<H2> BUGS </H2>
|
|
Hopefully not.
|
|
<H2> AUTHOR </H2>
|
|
Andreas Stolcke <stolcke@icsi.berkeley.edu>
|
|
<BR>
|
|
Copyright (c) 1998-2004 SRI International
|
|
</BODY>
|
|
</HTML>
|