SLIDE 1 Moving Object Trajectory Mining Moving Object Trajectory Mining
Trajectory decomposition algorithm Trajectory decomposition algorithm
Somayeh Dodge Robert Weibel
Representation Analysis and Dagstuhl, November 2008 Representation, Analysis and Visualization of Moving Objects
SLIDE 2
Initial idea
How similar proxy MPOs are to the di f MPO corresponding reference MPOs
HCI studies (mouse movement as a proxy of ( p y eye movement) (Chen et al,2001; Cox et al, 2006) Social science studies (bank note dispersal as Social science studies (bank note dispersal as human movement) (Gonzàles et al,2008)
Main goal: to reveal similarities between Main goal: to reveal similarities between physics of movement of different objects
SLIDE 3
Trajectory decomposition j y p
Aim: Local movement feature extraction
E t ti t t f t j t i f Extracting movement parameters from trajectories of MPOs
Input:
Movement parameter profile (e.g. speed, acceleration, p p ( g p , , straightness index, turning angle)
Output: Output:
Segments of homogeneous movement characteristics
SLIDE 4 Decomposition algorithm p g
Key elements: Key elements:
Variation in sinuosity Variation in deviation from median line Variation in deviation from median line
SLIDE 5 Decomposition outcome p
Dodge, S., Weibel, R., Forootan, E., (2008): Revealing the Physics of Movement: Comparing the Similarity of Movement Characteristics of Different Types of Moving Objects.. Under review of the "Spatial Data Mining: Methods and Applications", A Special Issue of the Journal of Computers, Environment and Urban Systems.
SLIDE 6
Applications (1) pp ( )
Classifying trajectory data generated by k i bj t d i i unknown moving objects and assigning them to known types of moving objects. yp g j Similarity analysis tasks
Finding similarities in movement behavior of Finding similarities in movement behavior of moving objects from the same or different types
SLIDE 7 Applications (1) - example pp ( ) p
Dodge, S., Weibel, R., Forootan, E., (2008): Revealing the Physics of Movement: Comparing the Similarity of Movement Characteristics of Different Types of Moving Objects.. Under review of the "Spatial Data Mining: Methods and Applications", A Special Issue of the Journal of Computers, Environment and Urban Systems.
SLIDE 8 Applications (2) pp ( )
Trajectory simulation
- in ecological modeling (Bl th
t l 1996 T hi
... in ecological modeling (Blythe et al., 1996; Turchin,
1998)
- in spatio temporal database research (Pf
&
... in spatio-temporal database research (Pfoser &
Theodoridis, 2003)
- in data mining algorithm evaluation (Laube &
... in data mining algorithm evaluation (Laube &
Purves, 2006)
Reproducing MPOs according to the global and local characteristics of objects having the same local characteristics of objects having the same dynamic behavior
SLIDE 9
Applications (3): Saccade and fixation
d t ti t t l detection on eye movement protocols
Fi ti Fixation Saccade
SLIDE 10
Thanks for your attention! y
