You can use the HMM model with the --hmm-align option for train-model.perl. The training scripts fails because you only changed the options of Giza without informing the script that it should not expect any *.A3 files. The --hmm-align option does this for you.
Also there is no reason why you could not produce alignment files using only model 1, you would just need to adjust the training script accordingly. The uniform distribution is assumed for the first initial step, parameters change to something more meaningful after several iterations of the EM algorithm. However, most probably pure Model 1 alignment won't be very good, as it incorporates no word-position-related information, the HMM model is much better usually. Some people claim, that you can abandon Model 3 and 4 altogether and stop after the HMM model. Best, Marcin W dniu 06.03.2014 21:29, John D. Burger pisze: > On Mar 6, 2014, at 16:00 , Momo Jeng <[email protected]> wrote: > >> I'm having a problem getting results from Moses, although I think it's >> really a problem with GIZA++; please let me know if there's a better place >> for GIZA questions. >> >> When I run Moses instructing GIZA++ to only do model1 and hmm iterations ( >> "--giza-option >> model1iterations=3,hmmiterations=3,model3iterations=0,model4iterations=0" ), >> Moses fails, because GIZA++ doesn't produce an alignment file (the .A3.final >> file). >> >> Based on a quick look at the GIZA++ code, this failure is explicit in the >> code. In main.cpp, m3.viterbi(...) is only called at line 652 if at least >> one iteration is set for model 3, 4, 5, or 6, and m3.viterbi(...) is where >> the code for writing the alignment file is called. So I'm wondering if this >> a bug, or by design. Is there some reason that I shouldn't create alignments >> without using model 3 or higher? > You can't produce actual alignments with Model 1 - it assumes a uniform > distribution from each word over all the words in the other half of the > sentence pair. It's really only useful for initializing the word translation > probabilities for one of the more sophisticated models. > > - JB > _______________________________________________ > Moses-support mailing list > [email protected] > http://mailman.mit.edu/mailman/listinfo/moses-support _______________________________________________ Moses-support mailing list [email protected] http://mailman.mit.edu/mailman/listinfo/moses-support
