phrase_query_indexing

In this project we construct phrase query retrieval using 20_newsgropus dataset

Getting Started

Before running the above code please make sure that, you have downloaded 20_newsgroups dataset which is freely available in the internet and place in the data folder. Now run the code cell by cell.

Installing

The following packages are used for the project

+ python 3
+ nltk for text processing
+ pickle for storing and loading data structures

Pre processing

+ Removal of meta data in each file
+ Removal of symbols like [!@#$%^&*()] from the tokens
+ Removal of non alpha numeric tokens
+ Lemmatization of tokens
+ Removal of words that are less than size 2 (useless words)

Methodology

• Positional Indexing is constructed for two folders rec.motorcycles, comp.graphics in 20_newsgroups dataset
• Preprocessing each file in the above folders
• Construction of the positional indexing dictionary. (Code is self explainatory with comments)
• when the user gives the query, we find the relative distance between tokens in the query and retrieve all the files which contains tokens in the same distance.

References

followed chris manning book for constructing the dictionary link