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Understand the similarity between two time series using Dynamic Time Warping (DTW) and Euclidean distance. Explore DTW complexity, constraints, and preprocessing techniques in this lecture. Includes examples and reference materials.
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Lecture 10.1 Time Series (Dis)Similarity (Dynamic Time Warping) CMSC 818W : Spring 2019 Tu-Th 2:00-3:15pm CSI 2118 Nirupam Roy Apr. 25th 2019
Similarity between two time series Signal A: Signal B:
Similarity between two time series: Euclidian distance Sqrt((a1-b1)2 + (a2-b2)2 ) (a1, a2) (b1, b2)
Similarity between two time series: Euclidian distance Signal A: N number of points Signal B: Euclidian distance:
Similarity between two time series: Euclidian distance Signal A: N number of points Signal B: Euclidian distance:
Similarity between two time series: Euclidian distance Euclidian distance
Similarity between two time series: Euclidian distance Desired approach
Similarity between two time series: Euclidian distance Desired approach
Dynamic Time Warping Slides by Quim LlimonaTorrashttps://lemonzi.files.wordpress.com/2013/01/dtw.pdf
DTW : An example [Citation] Slides take from Thales Sehn Körting https://www.youtube.com/watch?v=_K1OsqCicBY
|Ai-Bj| + min{ D[i-1,j-1], D[i-1,j], D[i,j-1]} |9-3| + min{ 5, 5, 11} = 6 + 5 = 11 A i B j
min{ D[i-1,j-1], D[i-1,j], D[i,j-1]} A i B j
min{ D[i-1,j-1], D[i-1,j], D[i,j-1]} A i B j
min{ D[i-1,j-1], D[i-1,j], D[i,j-1]} A i B j
DTW : Recap Reference: http://www.cs.ucr.edu/~eamonn/KAIS_2004_warping.pdf
DTW : Recap |Ai-Bj| + min{ D[i-1,j-1], D[i-1,j], D[i,j-1]} |9-3| + min{ 5, 5, 11} = 6 + 5 = 11 A i B j
min{ D[i-1,j-1], D[i-1,j], D[i,j-1]} A i B j
DTW : Complexity What is the complexity of DTW algorithm?
DTW : Constraints Slides by Quim LlimonaTorrashttps://lemonzi.files.wordpress.com/2013/01/dtw.pdf
A i B j