Shallow Parsing

Task Definition

Many language processing tasks do not require complex parse trees. Instead, a partial parse, or a shallow parse of a sentence is sufficient. Shallow parsing is the process of identifying flat non-overlapping parts of a sentence. These parts typically include Özne, Yüklem, Nesne, Zarf Tümleci, and Dolaylı Tümleç. Since a parsed text does not include a hierarchical structure, a bracketing notation is sufficient to denote the location and the type of shallow parse chunks in a sentence.

In shallow parsing, one tries to find the strings of text that belong to a chunk and to classify the type of that chunk. Standard approach for shallow parsing is a word-by-word classification, where the classifier is trained to label the words in the text with tags that indicate the presence of particular chunks. After giving the class labels to our training data chunk labels, the next step is to select a group of features to discriminate different chunks for each input word.

[_OZNE Türk Hava Yolları] [_{ZARF TÜMLECİ} Salı günü] [_NESNE yeni indirimli fiyatlarını] [_YÜKLEM açıkladı]

[_SUBJECT Turkish Airlines] [_PREDICATE announced] [_OBJECT new discounted fares] [_{ADVERBIAL CLAUSE} on Tuesday]

The Table below shows typical shallow parse tags and the questions asked to the predicate to identify the chunks for those tags.

Tag	Question
ÖZNE	Who, What
ZARF TÜMLECİ	When, How, Why
DOLAYLI TÜMLEÇ	Where, To/From whom
NESNE	What, Whom
YÜKLEM	Predicate

Data Annotation

Preparation

1. Collect a set of sentences to annotate.
2. Each sentence in the collection must be named as xxxx.yyyyy in increasing order. For example, the first sentence to be annotated will be 0001.train, the second 0002.train, etc.
3. Put the sentences in the same folder such as Turkish-Phrase.
4. Build the project and put the generated sentence-shallowparse.jar file into another folder such as Program.
5. Put Turkish-Phrase and Program folders into a parent folder.

Annotation

1. Open sentence-shallowparse.jar file.
2. Wait until the data load message is displayed.
3. Click Open button in the Project menu.
4. Choose a file for annotation from the folder Turkish-Phrase.
   
5. For each word in the sentence, click the word, and annotate the word with one of the ÖZNE, NESNE, DOLAYLI_TÜMLEÇ, ZARF_TÜMLECİ, YÜKLEM, NONE tags.
6. Click one of the next buttons to go to other files.

Classification DataSet Generation

After annotating sentences, you can use DataGenerator package to generate classification dataset for the Shallow Parsing task.

Generation of ML Models

After generating the classification dataset as above, one can use the Classification package to generate machine learning models for the Shallow Parsing task.

For Developers

Requirements

• Java Development Kit 8 or higher, Open JDK or Oracle JDK
• Maven
• Git

Java

To check if you have a compatible version of Java installed, use the following command:

java -version

If you don't have a compatible version, you can download either Oracle JDK or OpenJDK

Maven

To check if you have Maven installed, use the following command:

mvn --version

To install Maven, you can follow the instructions here.

Git

Install the latest version of Git.

Download Code

In order to work on code, create a fork from GitHub page. Use Git for cloning the code to your local or below line for Ubuntu:

git clone <your-fork-git-link>

A directory called ShallowParsing will be created. Or you can use below link for exploring the code:

git clone https://github.com/olcaytaner/ShallowParsing.git

Open project with IntelliJ IDEA

Steps for opening the cloned project:

• Start IDE
• Select File | Open from main menu
• Choose ShallowParsing/pom.xml file
• Select open as project option
• Couple of seconds, dependencies with Maven will be downloaded.

Compile

From IDE

After being done with the downloading and Maven indexing, select Build Project option from Build menu. After compilation process, user can run ShallowParsing.

From Console

Go to ShallowParsing directory and compile with

 mvn compile 

Generating jar files

From IDE

Use package of 'Lifecycle' from maven window on the right and from ShallowParsing root module.

From Console

Use below line to generate jar file:

 mvn install

Maven Usage

    <dependency>
        <groupId>io.github.starlangsoftware</groupId>
        <artifactId>ShallowParsing</artifactId>
        <version>1.0.1</version>
    </dependency>