Stanford coreference possessive pronoun - stanford-nlp

Does Stanford's coreference resolution module support resolution for possessive pronouns? For example, consider the following sentences.
"Sandra has 5 candies. Sandra gave all of her candies to Susan."
Would the coreference module be able to determine that "her" refers to "Sandra"? If so, what are the API calls to do this?

In general, yes it does. It fails for that particular example. It would need some debugging as to why, but it seems to do with the more complex “all of …” noun phrase. If you instead try:
Sandra has 5 candies. Sandra gave her candies to Susan.
in the demo at:
http://nlp.stanford.edu:8080/corenlp/process
you can see it working.
There’s nothing special about getting these mentions out in coref chains if they are recognized. It’s just like regular use of Coref — See, for instance, StanfordCoreNlpDemo.java.

Related

Search using Xapian Omega - with Wild Cards or Regular Expressions

We are confronting different search engines for our research
archives and having browsed the Xapian-Omega documentation, we
decided to try it out since the Omega option appears to be an
appropriate solution with several interesting search options.
We installed Xapian-Omega on a Linux Server (Deb 7) and tested
the setup with success. However we are unsure as to how one can
employ or perhaps even enable the use of Wild Cards or Regular
Expressions with Xapian-Omega.
We read that for Xapian one has to enable the Wild Card option
"QueryParser flags"
Could someone clarify this ?
ie. explain with or indicate a page with an example or two.
But we did not see much information regarding examples with Omega
CGI and although this latter runs well, wild card options
(such as * for the general wild card and ? as a single character),
do not seem to work as expected by default and they would be
useful, even though stemming and substrings etc may be functional.
Eg: It would be interesting to be able to employ standard simple
wild char searches with a certain precision such as :
medic* for medicine medical medicament
or with ? for single characters
Can Regexp be recognised with Omega ?
eg : sep[ae]r[ae]te(\w+)?
or searching for structured formats such as Email or Credit Card
Numbers or certain formula types in research papers etc.
In a note from Olly Betts long ago (Dev Mailing List) regarding
this one suggestion was to grep the index file but this would
defeat the RAD advantage of Omega.
Any examples of searches using Omega with Wild Cards or Regular
Expressions would be most appreciated ... even an indication of
a page where information regarding this theme is well presented
with examples illustrating how to develop advanced searches
using Xapian alone would be most welcome (PHP or Python perhaps).
(We are not concerned for the moment about the eventual
substantial increase in the size of the index size or in the
time to index the archive)
You can enable right-wildcards (such as "medic*") in Omega using $set{flag_wildcard,1} (covered in the Omegascript documentation), which enables FLAG_WILDCARD. There's a section in the user manual on using wildcards.
Xapian doesn't provide support for regular expression searching, although in theory I believe it would be possible to support, if potentially costly (depending on the regex). It would have to run the regular expression against unstemmed terms in the database, and then feed them into the search. Where it becomes difficult is if the regex expands to a lot of terms (eg just 'a' as a regex). There's also some subtlety in making it efficient; it's easy to jump through the term list to something with a constant prefix, and you'd want to take advantage of that if possible.
For your example of sep[ae]r[ae]te(\w+)?, it sounds like you actually want a combination of spelling correction (for the a-e substitutions, which you can enable using $set{flag_spelling_correction,1}) and stemming (for the trailing letters after 'te'; Omega defaults to English stemming, but that can be changed), or either wildcard or partial match support.
If you do need regular expressions for your use case, then I'd suggest bringing it up on the xapian-discuss mailing list. Xapian has moved on since the last discussion, and I believe it would be easier to build such support now than it was then.
James Ayatt: Thank you for your answer and help, my apologies for this belated reply, a distraction with other work.
We had already seen the Omegascript page but it was not clear to us how to employ these options with the CGI interface. Also the use of * seems to be for trailing chars, is that correct ? ie not for internal groups of words eg: omeg*ipt; there are cases where the stemming option would not be sufficient. We did not see an option for single wild chars, sometimes represented by ? in certain search engines. Could you comment here ?
Regarding the use of regular expressions we had immagined that it might not be quite as simple as one could hope. The examples mentioned in the preceding post were of course simple possible uses, there are of course many more. Your comment on using the stemming option seems appropriate.
In certain cases it could be interesting to enable some type of regexp option for the extraction of text forms, such as those mentioned. The quick extractiion of such text, perhaps together with some surrounding text could be very useful.
We will certainly try your proposal with the mailing list.
Thank you again.

Stanford CoreNLP demo and coreference resolution

Consider the below sentences:
Bats are the only mammals that can fly. They are also among the only mammals known to feed on blood.
Input them in the below link
http://nlp.stanford.edu:8080/corenlp/process
Coreference output does not show that the word They refers to Bats. Am I missing something basic?
Stanford's dcoref module has the pronoun 'they' hardcoded to be animate only, and presumably 'bat' is in the inanimate word list.
The animate restriction is probably justified for the newswire training data, but is not valid for general English.
You can change the animate list here https://github.com/stanfordnlp/CoreNLP/blob/master/src/edu/stanford/nlp/dcoref/Dictionaries.java#L155

Bing/Google/Flickr API: how would you find an image to go along each of 150,000 Japanese sentences?

I'm doing part-of-speech & morphological analysis project for Japanese sentences. Each sentence will have its own webpage. To make this page more visual, I want to show one picture which is somehow related to the sentence. For example, For the sentence "私は学生です" ("I'm a student"), the relevant pictures would be pictures of school, Japanese textbook, students, etc. What I have: part-of-speech tagging for every word. My approach now: use 2-3 nouns from every sentence and retrieve the first image from search results using Bing Images API. Note: all the sentence processing up to this point was done in Java.
Have a couple of questions though:
1) what is better (richer corpus & powerful search), Google Images API, Bing Images API, Flickr API, etc. for searching nouns in Japanese?
2) how do you select the most important noun from the sentence to do the query in Image Search Engine without doing complicated topic modeling, etc.?
Thanks!
Japanese WordNet has links to OpenClipart pictures. That could be another relevant source. They describe it in their paper called "Enhancing the Japanese WordNet".
I thought you would start by choosing any noun before は、が and を and giving these priority - probably in that order.
But that assumes that your part-of-speech tagging is good enough to get は=subject identified properly (as I guess you know that は is not always the subject marker).
I looked at a bunch of sample sentences here with this technique in mind and found it as good as could be expected. Except where none of those are used, which is rarish.
And sentences like this one, where you'd have to consider maybe looking for で and a noun before it in the case where there is no を or は. Because if you notice here, the word 人 (people) really doesn't tell you anything about what's being said. Without parsing context properly, you don't even know if the noun is person or people.
毎年 交通事故で 多くの人が 死にます
(many people die in traffic accidents every year)
But basically, couldn't you implement a priority/fallback type system like this?
BTW I hope your sentences all use kanji, or when you see はし (in one of the sentences linked to) you won't know whether to show a bridge or chopsticks - and showing the wrong one will probably not be good.

How can I add more tagged words to the Stanford POS-Tagger's trained models?

I haven't found anything in the documentation about adding more tagged words to the tagger, specifically the bi-directional one.
Thanks
At present, you can't. Model training is an all-at-one-time operation. (Since the tagger uses weights that take into account contexts and frequencies, it isn't trivial to add new words to it post hoc.)
There is a workaround. It is ugly but should do the trick:
build a list of "your" words
scan text for these words
if any matches found to POS tagging yourself (NLTK can help you here)
feed it to Stanford parser.
FROM: http://www.cs.ucf.edu/courses/cap5636/fall2011/nltk.pdf
"You can also give it POS tagged text; the parser will try to use
your tags if they make sense.
You might want to do this if the parser makes tagging
mistakes in your text domain."

Algorithms to recognize misspelled names in texts

I need to develop an application that will index several texts and I need to search for people’s names inside these texts. The problem is that, while a person’s correct name is “Gregory Jackson Junior”, inside the text, the name might me written as:
- Greg Jackson Jr
- Gegory Jackson Jr
- Gregory Jackson
- Gregory J. Junior
I plan to index the texts on a nightly bases and build a database index to speed up the search. I would like recommendation for good books and/or good articles on the subject.
Thanks
Check these related questions.
Algorithm to find articles with similar text
How to search for a person's name in a text? (heuristic)
Your question is incorrectly phrased. The examples do not indicate misspelling but change in the form of writing a full name.
And,
would your search expect to match on words like son with reference to the example?
would it expect to match bob when looking for a name called Robert?
Are you looking for things like this and this?
Ok, reading your comment suggests you do not want to venture into that.
For the record. Use a Bayesian filter. You may use mechanical truck for initializing your algorithm.

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