towards semantic trajectory outlier detection artur ribeiro de aquino 1 luis otavio alvares 1 chiara...
TRANSCRIPT
![Page 1: Towards Semantic Trajectory Outlier Detection Artur Ribeiro de Aquino 1 Luis Otavio Alvares 1 Chiara Renso 2 Vania Bogorny 1 1 1 Dep. de Matemática e Estatística](https://reader035.vdocuments.site/reader035/viewer/2022062519/5697bfbe1a28abf838ca2b40/html5/thumbnails/1.jpg)
1
Towards Semantic Trajectory Outlier
DetectionArtur Ribeiro de Aquino1
Luis Otavio Alvares1
Chiara Renso2
Vania Bogorny1
1Dep. de Matemática e Estatística – Universidade Federal de Santa Catarina (UFSC)
2KDD Lab – Pisa, Italy
![Page 2: Towards Semantic Trajectory Outlier Detection Artur Ribeiro de Aquino 1 Luis Otavio Alvares 1 Chiara Renso 2 Vania Bogorny 1 1 1 Dep. de Matemática e Estatística](https://reader035.vdocuments.site/reader035/viewer/2022062519/5697bfbe1a28abf838ca2b40/html5/thumbnails/2.jpg)
2
Summary
Introduction and Motivation
Problem
Objective
Proposal Definition Algorithm
Experimental Results
Related Works
Conclusion and Future Works
![Page 3: Towards Semantic Trajectory Outlier Detection Artur Ribeiro de Aquino 1 Luis Otavio Alvares 1 Chiara Renso 2 Vania Bogorny 1 1 1 Dep. de Matemática e Estatística](https://reader035.vdocuments.site/reader035/viewer/2022062519/5697bfbe1a28abf838ca2b40/html5/thumbnails/3.jpg)
3
Introduction and Motivation
![Page 4: Towards Semantic Trajectory Outlier Detection Artur Ribeiro de Aquino 1 Luis Otavio Alvares 1 Chiara Renso 2 Vania Bogorny 1 1 1 Dep. de Matemática e Estatística](https://reader035.vdocuments.site/reader035/viewer/2022062519/5697bfbe1a28abf838ca2b40/html5/thumbnails/4.jpg)
4
Introduction and Motivation
![Page 5: Towards Semantic Trajectory Outlier Detection Artur Ribeiro de Aquino 1 Luis Otavio Alvares 1 Chiara Renso 2 Vania Bogorny 1 1 1 Dep. de Matemática e Estatística](https://reader035.vdocuments.site/reader035/viewer/2022062519/5697bfbe1a28abf838ca2b40/html5/thumbnails/5.jpg)
5
Introduction and Motivation
Many trajectory patternsChasing [Siqueira, 2011]Frequent movements [Giannotti, 2007], [Trasarti
2011];Meeting, Leadership, Convergence, Recurrence,
Flocks [Laube, 2005];
![Page 6: Towards Semantic Trajectory Outlier Detection Artur Ribeiro de Aquino 1 Luis Otavio Alvares 1 Chiara Renso 2 Vania Bogorny 1 1 1 Dep. de Matemática e Estatística](https://reader035.vdocuments.site/reader035/viewer/2022062519/5697bfbe1a28abf838ca2b40/html5/thumbnails/6.jpg)
6
Introduction and Motivation
Some works focused on outliersUncommon behavior
Example [Lee, 2008] [Yuan, 2011] [Alvares, 2011] [Fontes, 2013]
![Page 7: Towards Semantic Trajectory Outlier Detection Artur Ribeiro de Aquino 1 Luis Otavio Alvares 1 Chiara Renso 2 Vania Bogorny 1 1 1 Dep. de Matemática e Estatística](https://reader035.vdocuments.site/reader035/viewer/2022062519/5697bfbe1a28abf838ca2b40/html5/thumbnails/7.jpg)
7
Problem
Existing works do not interpret the outliers
Application examplesPublic safetyTraffic engineering
Slow traffic Alternative routes
![Page 8: Towards Semantic Trajectory Outlier Detection Artur Ribeiro de Aquino 1 Luis Otavio Alvares 1 Chiara Renso 2 Vania Bogorny 1 1 1 Dep. de Matemática e Estatística](https://reader035.vdocuments.site/reader035/viewer/2022062519/5697bfbe1a28abf838ca2b40/html5/thumbnails/8.jpg)
8
Objective
Extend the work of Fontes [Fontes, 2013]
Outlier interpretation
Semantic classificationStop OutliersEvent Avoiding OutliersTraffic Avoiding Outliers
![Page 9: Towards Semantic Trajectory Outlier Detection Artur Ribeiro de Aquino 1 Luis Otavio Alvares 1 Chiara Renso 2 Vania Bogorny 1 1 1 Dep. de Matemática e Estatística](https://reader035.vdocuments.site/reader035/viewer/2022062519/5697bfbe1a28abf838ca2b40/html5/thumbnails/9.jpg)
9
Proposal
![Page 10: Towards Semantic Trajectory Outlier Detection Artur Ribeiro de Aquino 1 Luis Otavio Alvares 1 Chiara Renso 2 Vania Bogorny 1 1 1 Dep. de Matemática e Estatística](https://reader035.vdocuments.site/reader035/viewer/2022062519/5697bfbe1a28abf838ca2b40/html5/thumbnails/10.jpg)
10
Proposal
Fontes [Fontes, 2013]
![Page 11: Towards Semantic Trajectory Outlier Detection Artur Ribeiro de Aquino 1 Luis Otavio Alvares 1 Chiara Renso 2 Vania Bogorny 1 1 1 Dep. de Matemática e Estatística](https://reader035.vdocuments.site/reader035/viewer/2022062519/5697bfbe1a28abf838ca2b40/html5/thumbnails/11.jpg)
11
Definition:Stop Outlier
![Page 12: Towards Semantic Trajectory Outlier Detection Artur Ribeiro de Aquino 1 Luis Otavio Alvares 1 Chiara Renso 2 Vania Bogorny 1 1 1 Dep. de Matemática e Estatística](https://reader035.vdocuments.site/reader035/viewer/2022062519/5697bfbe1a28abf838ca2b40/html5/thumbnails/12.jpg)
12
Definition – Outlier Segment
![Page 13: Towards Semantic Trajectory Outlier Detection Artur Ribeiro de Aquino 1 Luis Otavio Alvares 1 Chiara Renso 2 Vania Bogorny 1 1 1 Dep. de Matemática e Estatística](https://reader035.vdocuments.site/reader035/viewer/2022062519/5697bfbe1a28abf838ca2b40/html5/thumbnails/13.jpg)
13
Definition – Stop Outlier
![Page 14: Towards Semantic Trajectory Outlier Detection Artur Ribeiro de Aquino 1 Luis Otavio Alvares 1 Chiara Renso 2 Vania Bogorny 1 1 1 Dep. de Matemática e Estatística](https://reader035.vdocuments.site/reader035/viewer/2022062519/5697bfbe1a28abf838ca2b40/html5/thumbnails/14.jpg)
14
Definitions:Event Avoiding Outlier
![Page 15: Towards Semantic Trajectory Outlier Detection Artur Ribeiro de Aquino 1 Luis Otavio Alvares 1 Chiara Renso 2 Vania Bogorny 1 1 1 Dep. de Matemática e Estatística](https://reader035.vdocuments.site/reader035/viewer/2022062519/5697bfbe1a28abf838ca2b40/html5/thumbnails/15.jpg)
15Definition – Standard Segment
![Page 16: Towards Semantic Trajectory Outlier Detection Artur Ribeiro de Aquino 1 Luis Otavio Alvares 1 Chiara Renso 2 Vania Bogorny 1 1 1 Dep. de Matemática e Estatística](https://reader035.vdocuments.site/reader035/viewer/2022062519/5697bfbe1a28abf838ca2b40/html5/thumbnails/16.jpg)
16Definition - Event Avoiding Outlier
![Page 17: Towards Semantic Trajectory Outlier Detection Artur Ribeiro de Aquino 1 Luis Otavio Alvares 1 Chiara Renso 2 Vania Bogorny 1 1 1 Dep. de Matemática e Estatística](https://reader035.vdocuments.site/reader035/viewer/2022062519/5697bfbe1a28abf838ca2b40/html5/thumbnails/17.jpg)
17
Definitions:Traffic Avoiding Outlier
![Page 18: Towards Semantic Trajectory Outlier Detection Artur Ribeiro de Aquino 1 Luis Otavio Alvares 1 Chiara Renso 2 Vania Bogorny 1 1 1 Dep. de Matemática e Estatística](https://reader035.vdocuments.site/reader035/viewer/2022062519/5697bfbe1a28abf838ca2b40/html5/thumbnails/18.jpg)
18Definition – Synchronized Standard Segment
![Page 19: Towards Semantic Trajectory Outlier Detection Artur Ribeiro de Aquino 1 Luis Otavio Alvares 1 Chiara Renso 2 Vania Bogorny 1 1 1 Dep. de Matemática e Estatística](https://reader035.vdocuments.site/reader035/viewer/2022062519/5697bfbe1a28abf838ca2b40/html5/thumbnails/19.jpg)
19Definition – Traffic Avoiding Outlier
![Page 20: Towards Semantic Trajectory Outlier Detection Artur Ribeiro de Aquino 1 Luis Otavio Alvares 1 Chiara Renso 2 Vania Bogorny 1 1 1 Dep. de Matemática e Estatística](https://reader035.vdocuments.site/reader035/viewer/2022062519/5697bfbe1a28abf838ca2b40/html5/thumbnails/20.jpg)
20
Algorithm
![Page 21: Towards Semantic Trajectory Outlier Detection Artur Ribeiro de Aquino 1 Luis Otavio Alvares 1 Chiara Renso 2 Vania Bogorny 1 1 1 Dep. de Matemática e Estatística](https://reader035.vdocuments.site/reader035/viewer/2022062519/5697bfbe1a28abf838ca2b40/html5/thumbnails/21.jpg)
21
Proposal - Algorithm
Main
![Page 22: Towards Semantic Trajectory Outlier Detection Artur Ribeiro de Aquino 1 Luis Otavio Alvares 1 Chiara Renso 2 Vania Bogorny 1 1 1 Dep. de Matemática e Estatística](https://reader035.vdocuments.site/reader035/viewer/2022062519/5697bfbe1a28abf838ca2b40/html5/thumbnails/22.jpg)
22
Proposal - Algorithm
findEventAvoidingOutlier
![Page 23: Towards Semantic Trajectory Outlier Detection Artur Ribeiro de Aquino 1 Luis Otavio Alvares 1 Chiara Renso 2 Vania Bogorny 1 1 1 Dep. de Matemática e Estatística](https://reader035.vdocuments.site/reader035/viewer/2022062519/5697bfbe1a28abf838ca2b40/html5/thumbnails/23.jpg)
23
Proposal - Algorithm
findTrafficAvoidingOutlier
![Page 24: Towards Semantic Trajectory Outlier Detection Artur Ribeiro de Aquino 1 Luis Otavio Alvares 1 Chiara Renso 2 Vania Bogorny 1 1 1 Dep. de Matemática e Estatística](https://reader035.vdocuments.site/reader035/viewer/2022062519/5697bfbe1a28abf838ca2b40/html5/thumbnails/24.jpg)
24
Experimental Results
![Page 25: Towards Semantic Trajectory Outlier Detection Artur Ribeiro de Aquino 1 Luis Otavio Alvares 1 Chiara Renso 2 Vania Bogorny 1 1 1 Dep. de Matemática e Estatística](https://reader035.vdocuments.site/reader035/viewer/2022062519/5697bfbe1a28abf838ca2b40/html5/thumbnails/25.jpg)
25
Experimental Results
Taxi trajectories in San Francisco
Split trajectories (occupation, weekdays)
537.098 trajectories with 6.314.120 points in total
maxDist = 100m
minSup = 5%
minLength = 10%
![Page 26: Towards Semantic Trajectory Outlier Detection Artur Ribeiro de Aquino 1 Luis Otavio Alvares 1 Chiara Renso 2 Vania Bogorny 1 1 1 Dep. de Matemática e Estatística](https://reader035.vdocuments.site/reader035/viewer/2022062519/5697bfbe1a28abf838ca2b40/html5/thumbnails/26.jpg)
26Experimental Results – Stop Outlier
minTime = 15 min
73 stop outliers
44:13 min of duration
![Page 27: Towards Semantic Trajectory Outlier Detection Artur Ribeiro de Aquino 1 Luis Otavio Alvares 1 Chiara Renso 2 Vania Bogorny 1 1 1 Dep. de Matemática e Estatística](https://reader035.vdocuments.site/reader035/viewer/2022062519/5697bfbe1a28abf838ca2b40/html5/thumbnails/27.jpg)
27Experimental Results – Event Avoiding Outlier
Event at Bayshore Freeway (US101)
From 17:30 to 21:30
![Page 28: Towards Semantic Trajectory Outlier Detection Artur Ribeiro de Aquino 1 Luis Otavio Alvares 1 Chiara Renso 2 Vania Bogorny 1 1 1 Dep. de Matemática e Estatística](https://reader035.vdocuments.site/reader035/viewer/2022062519/5697bfbe1a28abf838ca2b40/html5/thumbnails/28.jpg)
28Experimental Results – Traffic Avoiding Outlier
timeTol = 15 min
6 traffic avoiding outliers
Synchronized standard segments (avg): 7:05 min
Fastest standard segments (avg): 3:30 min
![Page 29: Towards Semantic Trajectory Outlier Detection Artur Ribeiro de Aquino 1 Luis Otavio Alvares 1 Chiara Renso 2 Vania Bogorny 1 1 1 Dep. de Matemática e Estatística](https://reader035.vdocuments.site/reader035/viewer/2022062519/5697bfbe1a28abf838ca2b40/html5/thumbnails/29.jpg)
29
Related Works
Lee, 2008
Yuan, 2011
Chen,
2011
Alvares,
2011
Fontes,
2013
Proposed
Time x x
Event x
Subtrajectory x x x x x x
Standard x x x
Outlier x x x x x
Standard Path x
Outlier Segment x
Standard Segment x
Semantics x
![Page 30: Towards Semantic Trajectory Outlier Detection Artur Ribeiro de Aquino 1 Luis Otavio Alvares 1 Chiara Renso 2 Vania Bogorny 1 1 1 Dep. de Matemática e Estatística](https://reader035.vdocuments.site/reader035/viewer/2022062519/5697bfbe1a28abf838ca2b40/html5/thumbnails/30.jpg)
30
Conclusion and Future Works
Lack of interpretation on previous approaches
New concepts were provided aiming the semantics
Cases found were correctly interpreted
Future…Weight to each outlier segmentOutlier classification based on their outlier segments
![Page 31: Towards Semantic Trajectory Outlier Detection Artur Ribeiro de Aquino 1 Luis Otavio Alvares 1 Chiara Renso 2 Vania Bogorny 1 1 1 Dep. de Matemática e Estatística](https://reader035.vdocuments.site/reader035/viewer/2022062519/5697bfbe1a28abf838ca2b40/html5/thumbnails/31.jpg)
31
Towards Semantic Trajectory Outlier
DetectionArtur Ribeiro de Aquino1
Luis Otavio Alvares1
Chiara Renso2
Vania Bogorny1
1Dep. de Matemática e Estatística – Universidade Federal de Santa Catarina (UFSC)
2KDD Lab – Pisa, Italy