Identifying Intention Posts in Discussion Forums Meichun Hsu - PowerPoint PPT Presentation

Identifying Intention Posts in Discussion Forums Meichun Hsu Zhiyuan (Brett) Chen Malu Castellanos Bing Liu Riddhiman Ghosh

What is Intention?

Example Hello, I am going to buy a new high-end gaming laptop my budget is below than 1500$ ram should be more than 6gb,graphics card must be more than 2gb and the processor should be intel core i7 3rd generations or better.

Explicit Intention I plan to buy this book. I am looking for a new car. I am going to travel to Atlanta.

Implicit Intention Anyone knows the battery life of iPhone? What are the components in this laptop?

Identifying Intention A totally NEW problem Explicit intention Applications like advertisement

Problem Definition

Two-Class Post Classification Transfer Learning: Use labeled data from other domains (source domains) to classify target domain

The ways to express an intention are similar in different domains.

Motivation Examples I want to buy a car. I want to buy a camera. I want to buy the tickets.

Special Difficulties

Noise I read many reviews of two Canon models which I'm considering for purchase, the Canon PowerShot S2 IS and the Canon PowerShot S3 IS. This is my second digital camera, my first being a Kodak EasyShare from about 4 years ago. …

Imbalanced Shared Features

EM Algorithm with NB (Nigam et al., 2000) E-step M-step Naïve Bayes

Proposed Models FS-EM Co-Class

FS-EM Incorporates feature selection into EM iterations Selects features from both labeled source (domain) data and unlabeled target (domain) data

Co-Class Builds two classifiers based on FS-EM Solves the imbalanced shared feature problem

Features & Feature Selection N-grams

Evaluation

Datasets 4 Domains from different forums (http://www.cs.uic.edu/~zchen/) Human annotation Cross-validation

Evaluation Measures

Supervised Learning (One Domain)

Model Comparisons 3TR-1TE (Aue & Gamon, 2005) EM (Nigam, et al., 2000) ANB (Tan et al., 2009) FS-EM1 FS-EM2 Co-Class

Model Comparisons

Effects of Source Domains

Conclusions Novel problem of identifying intention Suitable for transfer learning Two special difficulties Effectiveness of Co-Class

Future Directions Sentence-level classification Extract intention components

Q & A

Dataset Download Link: http://www.cs.uic.edu/~zchen/