context sensitive ppt

8/13/2019 Context Sensitive Ppt

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SPELL CHECKERBASIC AND CONTEXT

SENSITIVE

By:

K Satish Kumar ( 07131A0544 )

B Krishna Chaitanya (07131A0547 )

K Viswa Sai Raja ( 07131A0546)


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SPELL CHECKER:

A spell checkeris an application program that flags

words in a document that are not be spelt correctly.

Our application provides a method of correction of

misspelled and confused words in a phrase written in anatural language.

The application can offer several words as choice

words for inserting into the passage to replace the

unrecognized word.


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The kind of errors which result due to the absence of the

typed word in the dictionary are known as non-word

errors.

These kind of errors can be detected and corrected

using basic spell checking capabilities.

Examples: ths instead of this,

spel instead of spell

Basic Spell Checking


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BASIC SPELL CORRECTION APPROACH:

In order to perform basic spell checking, first we construct a trie with all the words that

are present in a dictionary. A dictionary is nothing but sequence of words in a text file.

After the trie is constructed then the given text which is either a single sentence or a

group of sentences is split into words. Then every word is searched for its presence inthe trie.

If any word is not found it is added to the misspelling list.

The suggestions to the words in this list are provided using edit distance criteria and

phonetic distance criteria.

In order to provide suggestions based on phonetic distance we are using a Class

called Double Metaphone from the package commons-codec-1.3provided by apache

software foundation group.


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HOW OUR SPELL CHECKER IS DIFFERENT FROM REGULAR

SPELL CHECKER???

I saw TREI trees in the parkINPUT

REGULAR

SPELL

CHECKER

I saw [ TREE | TREK ] trees in the park


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INPUT I saw TREE trees in the park

CONTEXTSENSITIVE

SPELL

CHECKER

I saw THREE trees in the park


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Recently, research has focused on developing algorithms which are capableof recognizing a misspelled word, even if the word itself is in the vocabulary,

based on the context of the surrounding words.

The detection and correction of spelling mistakes that result in real words of

the target language, also known as real word spell checking, is the mostchallenging task for a spell checking system.

However, the majority of those systems are not able to catch the kind of

errors such as in Let us meat today (meat was typed when meet was

intended). This kind of spell checking is known as Context sensitive spell

checking.

Indeed, empirical studies have estimated that errors resulting in valid words

account from 25% to more than 50% of the errors, depending on the

application.

Context Sensitive Spell Checking


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Context Sensitive Spell Check Approach:

In order to perform context based spell checking we are

taking the help of a search engine. It can be of Google or

Yahoo! or Bing or any other which allows to access the search

results of the query through an API.

Yahoo! provides the users an api through which we can give

unlimited number of queries once we have registered with

Yahoo!! BOSS. So finally we are using the search power of

Yahoo!.

Yahoo! Search BOSS (Build your Own Search Service) is aninitiative in Yahoo!! Search to open up Yahoo!!'s search

infrastructure and enable third parties to build revolutionary

search products leveraging their own data, content, technology,

social graph, or other assets.


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In this project, we send requests to the Yahoo! Boss Web

Service to find the possible real word error in the given sentence.

Consider the following sentence,

Let us meat today

The above sentence will be sent to the Yahoo! web server in the following

formats.

* us meat today

Let * meat today

Let us * today

Let us meat *

Context Sensitive Spell Check Approach:


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HOW TO USE THE YAHOO SERVICE:

The Yahoo! web server returns the result count for each sentence

sent. Basing on the number of results received from the web server,

we estimate the possible real word in the given sentence.

After the error has been detected, we generate suggestions basing on

features such as Edit Distance and Phonetic Distance.

But during the testing phase of the spell checking application, we

stored the most likely confused words, so that we need not consider the

above features and check with the most likely confused pair of the word

itself.


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Yahoo BOSS Application ID


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MAIL FEATURE:

JavaMail is a Java API used to receive and send email via SMTP,

POP3 and IMAP. JavaMail is built into the Java EE platform, but also

provides an optional package for use in Java SE.

The JavaMail API provides a platform-independent and protocol-

independent framework to build mail and messaging applications.

In our project, we are providing the users with an option to send the

Spell Checked text to the users mail account. We use the JavaMail

API to send the text content to the mentioned Email Address.


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USE CASE DIAGRAM:


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CLASS DIAGRAM:


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ACTIVITY DIAGRAM:


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SEQUENCE DIAGRAMS:

1.USERAPPLICATION:


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2.USERAPPLICATION - WEBSERVICE:


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3.USERAPPLICATION (MAIL):


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SCREEN SHOTS:


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OPENFILE DIALOGUE:


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OPENED DOCUMENT:


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REPLACING MISSPELLINGS:


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WHAT IF NO SUGGESTION FOUND:


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ADD TO DICTIONARY:


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Context Sensitive Spell

Checking


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MAIL FEATURE:


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REQUEST DETAILS DIALOGUE:


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Mail Received


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CONCLUSION:

This spell checker can be used when we need a rigorous checking ofour text (like when sending the document to higher officials etc.)

The Yahoo! BOSS API does not permit large number of requests inshort time. For this purpose we used a delay of 9 sec betweenconsecutive requests. This is to be reduced.

Besides this the result of our question greatly depends on the searchresults from search engine. Sometimes the required pattern may not befound in the search result.

So the future enhancements can be made such as using our owndatabase. A Database size of about 200GB can be made with the helpof Google trigram datasets and match the sentence against the trigramsto find out the central word and offer the suggestions based on featuressuch as edit and phonetic distances.

context sensitive ppt

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