Title
Visual exploration of frequent patterns in multivariate time series
Abstract
The detection of frequently occurring patterns, also called motifs, in data streams has been recognized as an important task. To find these motifs, we use an advanced event encoding and pattern discovery algorithm. As a large time series can contain hundreds of motifs, there is a need to support interactive analysis and exploration. In addition, for certain applications, such as data center resource management, service managers want to be able to predict the next day's power consumption from the previous months' data. For this purpose, we introduce four novel visual analytics methods: {i} motif layout - using colored rectangles for visualizing the occurrences and hierarchical relationships of motifs; {ii} motif distortion - enlarging or shrinking motifs for visualizing them more clearly; {iii} motif merging - combining a number of identical adjacent motif instances to simplify the display; and {iv} pattern preserving prediction - using a pattern-preserving smoothing and prediction algorithm to provide a reliable prediction for seasonal data. We have applied these methods to three real-world datasets: data center chilling utilization, oil well production, and system resource utilization. The results enable service managers to interactively examine motifs and gain new insights into the recurring patterns to analyze system operations. Using the above methods, we have also predicted both power consumption and server utilization in data centers with an accuracy of 70-80%.
Year
DOI
Venue
2012
10.1177/1473871611430769
Information Visualization
Keywords
Field
DocType
motif distortion,multivariate time series,data center resource management,service manager,power consumption,identical adjacent motif instance,motif layout,data center,chilling utilization,frequent pattern,data stream,visual exploration,seasonal data,service management,merging,resource manager,prediction,visual analytics,seasonality,distortion,resource utilization,time series
Resource management,Data mining,Data stream mining,Computer science,Visual analytics,Motif (music),Smoothing,Data center,Distortion,Encoding (memory)
Journal
Volume
Issue
ISSN
11
1
1473-8716
Citations 
PageRank 
References 
16
0.72
12
Authors
8
Name
Order
Citations
PageRank
Ming C. Hao125622.55
Manish Marwah267250.11
Halldor Janetzko331220.69
Umeshwar Dayal484522538.92
Daniel A. Keim577041141.60
Debprakash Patnaik619114.89
Naren Ramakrishnan71913176.25
Ratnesh K. Sharma848353.37