Semantic Parser¶

Semantic parser is used to translate text representation into formal language representation. The aim is to be able to process user utterances and react upon them.

roboy_parser is based on SEMPRE <http://nlp.stanford.edu/software/sempre/. It is currently being modified to fulfill Roboy Dialog system needs.

Installation¶

In order to use semantic parser, you need to:

clone roboy_parser repository:

git clone http://github.com/Roboy/roboy_parser

navigate to created repository:
```
cd roboy_parser
```
build it:
```
ant freebase
```
run it:
```
./quick_start [options]
```

Architecture¶

Semantic parser is based on the language model and NLP algorithms that then apply rules to the utterance to translate it. Language model consists of: - set of grammar rules, - lexicon, - training dataset.

General architecture can be seen on the diagram below.

alt:	Semantic parser general architecture

Implementation¶

roboy_parser is a separate Java project and is communicating using WebSocket. Dialog system has a client implemented in SemanticParserAnalyzer.java class. It is therefore part of Natural Language Understanding unit.

Functionalities¶

Roboy parser currently has currently following functionalities:

Semantic Parser algorithms used¶
Functionality	Software used	Summary
POS Tags	OpenNLP	Tagging tokens as part of speech
NER Tags	OpenNLP	Tool used to tag named entities like PERSON, NUMBER, ORGANIZATION
Triple extraction	OpenIE	Tool used to extract triples from sentences in form `(Subject,Predicate,Object)`

Usage¶

In order to run the parser, you need to run roboy_parser first - see instructions on project Github <http://github.com/Roboy/roboy_parser and then run Dialog System.

Configurations¶

To test parser, you can run following configurations using quick_start.sh script. For more information refer to project documentation <http://github.com/Roboy/roboy_parser

Possible parser configurations¶
Command	Options
./quick_start	Default configuration. Using custom Roboy grammar and lexicons
./quick_start freebase	Example setup to test Freebase functionality