Post on 08-Jan-2016
description
Introduction and Motivation
On the Semantic Annotation of Places in Location-Based Social Networks
Mao Ye1, Dong Shou1, Wang-Chien Lee1, Peifeng Yin1, Krzysztof Janowicz2
Problem Description
Location-based Social Networks
E.g., Facebook Place and Foursquare
User check-in places
SAP Framework
1Department of Computer Science and EngineeringThe Pennsylvania State University
{mxy177,dus212,wlee,pzy102}@cse.psu.edu
2Department of GeographyUniversity of California, Santa Barbara
{jano}@geog.ucsb.edu
Tags are important
Business categorization
Location search
Place recommendation
Data cleaning
…
Tags are missing
In our Foursquare and Whirrl dataset, there are a lot of places missing tags
Places missing tags
Places with tags
Places missing tags
Places with tags
Foursquare Whrrl
67%
33%
68%
32%
Place semantic annotation (SAP) problem
Multi-label classification problem
Input
User check-in logs <who, where, when>
Some places are tagged
Output
Infer tags for the rest places
Check-in logs
PlacePlaceFeature Extraction (FE)
ComponentFeature Extraction (FE)
Component
Binary ClassifierFor tag t1
Binary ClassifierFor tag t1
Binary ClassifierFor tag t2
Binary ClassifierFor tag t2
Binary ClassifierFor tag tm
Binary ClassifierFor tag tm
Feature extraction (FE)
Check-in logs features
Features to describe a place
FE- Explicit Pattern FE- Implicit Relatedness
00:00
23:59
Day 1 Day 2 Day 3 Day 4 Day 5 Day 6 Day 7 Day 8
BarsBars BarsBars
BarsBars
RestaurantRestaurantRestaurantRestaurant RestaurantRestaurant
RestaurantRestaurant
RestaurantRestaurant
RestaurantRestaurant
RestaurantRestaurant RestaurantRestaurantRestaurantRestaurant
RestaurantRestaurant
ShoppingShopping ShoppingShopping
ShoppingShopping
GymGym HealthHealthBeautyBeauty
SpaSpa
Places checked in by the same user at around the same time (not necessarily the same day) are probably in the same category
?
EvaluationWhrrl.com. 5,892 users, 53,432 places and 199 types of tags According to Yelp, we map 199 tags into 21 categories.
Comparison: EP, IR and SAP (EP+IR)