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From vijay garla <vnga...@gmail.com>
Subject Re: sentence detector newline behavior
Date Thu, 23 Jan 2014 12:22:15 GMT
Just to clarify - with the YTEX branch there are 2 sentence splitter - the
original ctakes sentence that splits on newlines, and the ytex sentence
splitter that doesn't.  the changes to other components in the ytex branch
(dependency parser, assertion) work with both sentence splitters.

I think it would be great if the intelligence regarding how to split was in
the opennlp model, but this requires training data.  I don't know what the
training data is, or if the training data has sentences that cross newline
boundaries (if not, won't buy us anything).

vijay




On Wed, Jan 22, 2014 at 3:47 PM, Finan, Sean <
Sean.Finan@childrens.harvard.edu> wrote:

> On  my end it looks like my email was reformatted and some of my -newline-
> removed in those last examples ...
>
> -----Original Message-----
> From: Finan, Sean [mailto:Sean.Finan@childrens.harvard.edu]
> Sent: Wednesday, January 22, 2014 3:42 PM
> To: dev@ctakes.apache.org
> Subject: RE: sentence detector newline behavior
>
> Thanks James
>
> > but then no typical sentence ending punctuation at the end of the line
>
> Gotcha.
>
> > So simply using Lines would not suffice in those cases because it
> > would run together sentences where there are more than one on a line
>
> I was actually thinking about something like a Line using -sentence
> breaks- in addition to -newline-.  In other words, a Sentence being what
> cTakes detects by ignoring CR/LF, and Lines being those Sentences
> subdivided by -newline-.  Perhaps "Line" is a horrible moniker.
> Regardless, it doesn't solve the problem of inappropriately missing
> punctuation.  I was focused a little more on the difference between
> persistent auto- line wrapping and structured information like lists, where
> the first benefits from Sentence and the second from Line.
>
> "The Patient has
>  been prescribed two
>  medications."
>
> "Prescriptions:
>   Advil
>   Tylenol
>   No Aspirin"
>
>
> However, when it comes to the problem that you mention, there is no
> benefit to a Line.
>
> "The patient has been seen six times in the past week.  Pain has been
> persistent for ten days Advil and Tylenol have been prescribed"
> -- 2 sentences, 3 lines
>
>
> "The patient has been seen six times in the past week.
> Pain has been persistent for ten days
> Advil and Tylenol have been prescribed"
> -- 2 sentences, 3 lines
>
> "The patient has been seen six times in
>  the past week.  Pain has been persistent  for ten days  Advil and Tylenol
> have been prescribed"
> -- 2 sentences, 5 lines
>
> Nothing can really be done for the last bit where punctuation is missing.
>
>
>
>
> -----Original Message-----
> From: Masanz, James J. [mailto:Masanz.James@mayo.edu]
> Sent: Wednesday, January 22, 2014 3:07 PM
> To: 'dev@ctakes.apache.org'
> Subject: RE: sentence detector newline behavior
>
>
> I know there are notes where there are multiple sentences on a line, but
> then no typical sentence ending punctuation at the end of the line (or no
> punctuation at all at the end of the line). And in those sections, negation
> can be important.  So simply using Lines would not suffice in those cases
> because it would run together sentences where there are more than one on a
> line. And using sentences alone (as found by OpenNLP 1.5) would not suffice
> because it would run together sentences from different lines.
>
> -----Original Message-----
> From: Finan, Sean [mailto:Sean.Finan@childrens.harvard.edu]
> Sent: Wednesday, January 22, 2014 1:33 PM
> To: dev@ctakes.apache.org
> Subject: RE: sentence detector newline behavior
>
> Just whistling in the wind here ...
>
> Perhaps before any changes are made to universally toggle cTakes in one
> direction or the other, we can take a poll of when & where
> cTakes/Ytex/OpenNLP/Omaha needs a Sentence (ignoring CR/LF) as opposed to a
> Line (CR/LF delimited PLUS -sentence-)
>
> If some capabilities like negation detection require -lines- then would it
> make more sense to have Sentence ignore -newline- and negation detection
> itself split the Sentence into line items?  If an annotator is interested
> in list items, each of which may be on a distinct -line-, then it can split
> up the Sentence as needed.  I think that James hints that cTakes code
> already does this in some places.
>
> If a good deal of functionality requires -newline- delimited types, would
> it make sense to introduce a type Line?  If something uses a structured
> list it could iterate through Line types, while something using pure text
> could iterate through Sentence types.  This facilitates section-by-section
> different behavior, does not require any decision on global defaults, and
> makes data selection for training Sentence a nonesuch wrt line breaks.
>  However, it adds to the system and would require a per-use choice decision
> by developers OR a toggle by users (back to the default decision).
> Perhaps this has already been tried?
>
> Sean
>
>
> -----Original Message-----
> From: Masanz, James J. [mailto:Masanz.James@mayo.edu]
> Sent: Wednesday, January 22, 2014 1:06 PM
> To: 'dev@ctakes.apache.org'
> Subject: RE: sentence detector newline behavior
>
> The only rule I know of is that cTAKES (prior to ytex integration) always
> forces a sentence break at a newline.
> This was because the clinical notes cTAKES original processed never had
> newlines in the middle of a sentence, but did need sentence breaks to occur
> at end of sentence for good negation detection on those notes.
> I think Guergana earlier mentioned other EMRs also have this need, but it
> seems to not be ubiquitous.
>
> From others' posts, it seems that we could use an option in cTAKES to turn
> off this forcing of sentence breaks at newlines (or depending on how you
> look at it, an option to turn on the forcing of sentence breaks if we
> change the default behavior)
>
> I think we (cTAKES) need to decide the following:
>  - do we want to do this for entire notes, or would it be  worth it to
> have it be on a section-by-section basis.
>  - what do we make the default behavior - to force or not to force
> newlines to be sentence breaks
>  - what data (that contains newlines) will we use for training the
> sentence detector
>
> Regardless of those answers, I think OpenNLP support for including
> newlines in training data would be valuable for those others who have
> sentences that span lines.  And having an option on OpenNLP to always break
> at newline would be useful for at least some cTAKES users (and we could
> remove the cTAKES code that does that)
>
> -- James
>
> -----Original Message-----
> From: dev-return-2390-Masanz.James=mayo.edu@ctakes.apache.org [mailto:
> dev-return-2390-Masanz.James=mayo.edu@ctakes.apache.org] On Behalf Of
> Jörn Kottmann
> Sent: Tuesday, January 21, 2014 4:29 AM
> To: dev@ctakes.apache.org
> Subject: Re: sentence detector newline behavior
>
> Yes, exactly, OPENNLP-602 is about training a sentence detector model
> which can use a new line as a end-of-sentence character.
>
> In case you have certain rules to split sentences we should have a look at
> them. The Sentence Detector could be extended to support a user provided
> rule based splitter. If there is an interest in that we could probably get
> it into 1.6.0 as well.
>
> Jörn
>
> On 01/20/2014 10:02 PM, Chen, Pei wrote:
> > I presume Joern was suggesting that if he supports new lines in the
> opennlp SentenceDectector (either part of the trained models or post
> processing with some rules?) cTAKES will be able to use it out of the box
> and we should be able remove any additional custom logic that we currently
> have- which seems like a good idea.
> >
> > [but when to use within cTAKES individual components such as negation
> > might be another discussion?] --Pei
> >
> >> On Jan 20, 2014, at 12:46 PM, "vijay garla" <vngarla@gmail.com> wrote:
> >>
> >> The sentence detection opennlp model used by ctakes does not split
> >> sentences at newlines - there is additional logic in the takes
> >> sentence splitter that does this (and an alternative impl that
> >> doesn't is in the ytex branch). Afaik no retraining / change to the
> >> feature representation is necessary.
> >>
> >> Vj
> >>
> >>> On Monday, January 20, 2014, Jörn Kottmann <kottmann@gmail.com> wrote:
> >>>
> >>> Hi all,
> >>>
> >>> currently I have quite a bit of time to work on OpenNLP, and would
> >>> like to help you out with this issue.
> >>>
> >>> Here is the follow up issue for this change:
> >>> https://issues.apache.org/jira/browse/OPENNLP-602
> >>>
> >>> I am still trying to figure out what would be the best option to
> >>> implement this.
> >>> In the training data a user could just use a special tag to identify
> >>> the chars.
> >>>
> >>> Instead of <NEWLINE> it might be better to use <CR> and <LF>
to
> >>> encode these two chars in the training data. Any thoughts?
> >>>
> >>> I am planning to release this as part of OpenNLP 1.6.0.
> >>>
> >>> Thanks,
> >>> Jörn
> >>>
> >>>> On 05/22/2013 02:03 PM, Jörn Kottmann wrote:
> >>>>
> >>>>> On 05/22/2013 01:17 PM, Miller, Timothy wrote:
> >>>>>
> >>>>> That's awesome! It might be worth trying at least. How does the
> >>>>> training process change? Previously the training data would be one
> >>>>> sentence per line, but with newlines as possible mid-sentence
> >>>>> characters that could be trouble, is there a new representation
> >>>>> for training data? Or would we have to use the training api?
> >>>> Good point, yes that will be a problem with the default training
> >>>> format, but it shouldn't be hard to solve. In the format itself we
> >>>> could define a new line tag e.g.
> >>>> <NEWLINE> to mark new lines.
> >>>> as a hack to make it work with 1.5.3 you could instead use a
> >>>> special char as a replacement for the new line char.
> >>>> When you pass the text down to the sentence detector a simple
> >>>> string replace could be used to convert all new line chars to the
> >>>> special new line marker char.
> >>>>
> >>>> If things work out for you performance wise as well we will just
> >>>> integrate it properly into OpenNLP for the next release.
> >>>>
> >>>> Could you produce a sentence detector training file with a new line
> >>>> marker char?
> >>>>
> >>>> You should try to pick a char you can also pass in on a terminal
> >>>> otherwise you have to use the API to train the model. The build in
> >>>> cross validation could be used to evaluate the performance.
> >>>>
> >>>> Jörn
> >>>
>
>

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