[Attempto] Parsing questions and affirmations

[Norbert E. Fuchs]

> On 14 Dec 2019, at 12:48 , Marco Zanchi <mzanchi at gmail.com> wrote:
> 
> Hi there,
> 
> I have been playing with the parser recently and noticed a strange behaviour, not sure if it is down to the language definition or not. I can ask a question:
> 
> Is the project Alpha late?
> 
> And this parses well:
> 
> <DRS domain="">
>   <Question>
>     <DRS domain="A B">
>       <object
>  ref="B"
>  noun="project"
>  struct="countable"
>  unit="na"
>  numrel="eq"
>  num="1"
>  sentid="1"
>  tokid="3"/>
>       <predicate
>  ref="A"
>  verb="be"
>  subj="B"
>  obj="named('Alpha')"
>  sentid="1"
>  tokid="1"/>
>       <modifier_adv ref="A" adverb="late" degree="pos" sentid="1" tokid="5"/>
>     </DRS>
>   </Question>
> </DRS>
> 
> But if I try the equivalent affirmation:
> 
> The project Alpha is late.
> 
> then I get a parsing error.
> ERROR: [sentence] at 1-4: 'The project Alpha <> is late.'. This is the first sentence that was not ACE. The sign <> indicates the position where parsing failed.
> 
> Has anyone encountered anything of the sort?
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Marco

There is a grammar error occurring in both of your examples. Namely

	Variables can be introduced as noun phrase apposition, and can then be used as noun phrases. 
	Variable names consist of a single upper case letter, optionally followed by an integer.

Thus your noun phrase "project Alpha" violates this construction rule since "Alpha" is not a correct variable.

However, your first example "Is the project Alpha late?" points to a bug of the parser APE since - though being translated – it is translated wrongly as the DRS

[]
   QUESTION
   [A,B]
   object(B,project,countable,na,eq,1)-1/3
   predicate(A,be,B,named(Alpha))-1/1
   modifier_adv(A,late,pos)-1/5

that does nor reflect the question correctly. Again, the variable "Alpha" should trigger an error message.

Best regards.

Norbert E. Fuchs
Institute of Computational Linguistics
University of Zurich