Hi, these default scores were added fairly recently, so they do not work for version 2.0.
-phi On Thu, May 7, 2015 at 7:53 AM, Tomas Fulajtar <[email protected]> wrote: > Hi, > > > > Thanks for an excellent explanation. Does this “default-scores” parameter > work in 2.x release as well? > > > > Tomas > > > > > > From: Philipp Koehn [mailto:[email protected]] > Sent: Thursday, May 7, 2015 3:22 AM > To: [email protected] > Cc: [email protected] > Subject: Re: [Moses-support] Multiple Translation Tables and Back-off Models > in Moses > > > > Hi, > > > > I added a section to the Moses documentation on how to deal with this > situation: > > > > http://www.statmt.org/moses/?n=Advanced.Models#ntoc5 > > > > -phi > > Caveat: Multiple Translation Tables and Lexicalized Reordering You may > specify any number of lexicalized reordering models. Each of them will score > any translation option, no matter where it comes from. If a lexicalized > reordering table does not have an entry for a translation options, it will > not assign any score to it. In other words, such a translation option is > given the probability 1 no matter how it is reordered. This may not be the > way you want to handle it. > > For instance, if you have an "in-domain" translation table and an > out-of-domain translation table, you can also provide an in-domain > reordering table and anout-of-domain reordering table. If a phrase pair > occurs in both translation tables, it will be scored by both reordering > tables. However, if a phrase pairs occurs only in one of the phrase tables > (and hence reordering tables), it will be only score by one of them and get > a free ride with the other. this will have the undesirable effect of > discouraging phrase pairs that occur in both tables. > > To avoid this, you can add default scores to the reordering table: > > LexicalReordering name=LexicalReordering0 num-features=6 > type=wbe-msd-bidirectional-fe-allff [...] > default-scores=0.5,0.3,0.2,0.5,0.3,0.2 > > LexicalReordering name=LexicalReordering1 num-features=6 > type=wbe-msd-bidirectional-fe-allff [...] > default-scores=0.5,0.3,0.2,0.5,0.3,0.2 > > > > > > On Wed, May 6, 2015 at 3:00 AM, <[email protected]> wrote: > > Hi, > > > > I am studying moses to do some research abou SMT. I have read advanced > models in moses at the website > http://www.statmt.org/moses/?n=Advanced.Models#ntoc5 . I have some questions > about the introduction of "Multiple Translation Tables and Back-off Models". > > > > From the website, I know that moses allows the use of multiple translation > tables. But the lexicalized reordering model is not mentioned in the > introduction of "Multiple Translation Tables and Back-off Models". So, could > I use two translation tables, which I denote translation table1 and > translation table2 respectively, and one lexicalized reordering table > according to the introduction of "Multiple Translation Tables and Back-off > Models"? The phrase pairs in reordering table is the same with translation > table1, but not the same with translation table2. > > > > When I use multiple translation tables and only one reordering table, a > phrase pair may exist in only one translation table and don't exist in the > reordering model, how to calculate the probability of lexicalized reordering > model? > > > > I'm sorry for bothering you. Thanks and Best Regards, > > > > Zhenxin > > > > > _______________________________________________ > 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
