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)