SLIDE 1 Modeling of Human Movement Behavioral Knowledge from GPS Traces for Categorizing Mobile Users
S O U R S E : W W W 2 0 1 7 A D V I S O R : J I A - L I N G KO H S P E A K E R : H S I U - Y I , C H U D AT E : 2 0 1 7 / 1 1 / 7
SLIDE 2
Outline
Introduction Method Experiment Conclusion
SLIDE 3
Introduction
Question
Can we map the knowledge of one known region to another unknown(target) region and use this knowledge to categorize the users in the target region?
SLIDE 4 Introduction
Goal
Labeled GPS log Unlabeled GPS log
User category label
Knowledge
SLIDE 5
Outline
Introduction Method Experiment Conclusion
SLIDE 6
Method
SLIDE 7
Method
User Trajectory Segment
<S[], W[], Traj_Win[]>
S[]: list of stay points, s = <lat, lon, Geotagg> W[]: list of waiting points, w = <lat,lon> Traj_Win[]: {S1, (x1,x2), (x2,y2), … ,S2}
SLIDE 8
Method
User Trajectory Segment
SLIDE 9
Method
Semantic Stay Point Taxonomy(SSPTaxonomy)
SSPTaxonomy:<N, Nc, W>
N: place type of the Taxonomy
Nc: associated code of the node place W: aggregated footprints of user
SLIDE 10
Method
Semantic Stay Point Taxonomy(SSPTaxonomy)
SLIDE 11
Method
User-Trace Summary(UTS)
NB = <G,Θ>,G=<V,E>
v1i: (Nc,ti) Nc: associated code of the node place ti: temporal value of the node ei: dependences between the vertices
SLIDE 12
Method
User-Trace Summary(UTS)
Bayesian Network
SLIDE 13
Method
Θx5|Pax5 = 0.46
SLIDE 14
Method
Θx4|Pax4*Θx5|Pax5*Θx2|Pax2 = 0.6*0.46*0.98=0.27048
SLIDE 15 Method
Temporal Common Sub-sequence, (TempCS)clustering algorithm
Similarity measure(Bhattacharyya distance):
DB(X4, X5)=-ln{[X4(0)X5(0)]1/2+[X4(1)X5(1)]1/2}=
- ln{[0.4*(0.4*0.32+0.6*0.54)]1/2+[0.6*(0.4*0.68+0.6*0.46)]1/2}
SLIDE 16
Method
Temporal Common Sub-sequence, (TempCS)clustering algorithm
NB1:X4X3X5X1X2 NB2:X4X1X6X5X2 Common stay points(Lc):X4X5X2X1 Common Sub-sequence(Ls):X4X5X2
SLIDE 17
Method
Similarity between NB1and NB2: SimSequence(NB1,NB2)= 3/4[DB(X4, X5)+ DB(X5, X2)]
SLIDE 18
Method
User Categorization
Classification task:
PVu= {p1,p2,…,pi} i: user-category pi: probability of the user u in category i
SLIDE 19
Method
User Categorization
Feature
f1: visit in types of places f2: Speed of movement or transportation mode f3: User Movement
SLIDE 20
Method
User Categorization
Bayesian network
When independent Weighting each of feature
SLIDE 21
Method
Transfer Learning
SLIDE 22
Method
Transfer Learning
Extract the parent’s code cp of a node c. Node c has n sibling, append n+1 along with the parent’s code cpn+1. Check whether the same place-type in and assign the same code if present. Generate Get the common taxonomy
SLIDE 23
Outline
Introduction Method Experiment Conclusion
SLIDE 24
Experiment
Dataset
SLIDE 25
Experiment
Accuracy of User-Classification
SLIDE 26
Experiment
SLIDE 27
Outline
Introduction Method Experiment Conclusion
SLIDE 28
Conclusion
Address the user categorization problem from the GPS traces of the users. Propose a framework to model individual’s movement patterns. Transfer knowledge base from one city domain to another unknown city.