A Multiresolution Symbolic Representation of Time Series

Efficiently and accurately searching for similarities among time series and discovering interesting patterns is an important and non-trivial problem. In this paper, we introduce a new representation of time series, the Multiresolution Vector Quantized (MVQ) approximation, along with a new distance function. The novelty of MVQ is that it keeps both local and global information about the original time series in a hierarchical mechanism, processing the original time series at multiple resolutions. Moreover, the proposed representation is symbolic employing key subsequences and potentially allows the application of text-based retrieval techniques into the similarity analysis of time series. The proposed method is fast and scales linearly with the size of database and the dimensionality. Contrary to the vast majority in the literature that uses the Euclidean distance, MVQ uses a multi-resolution/hierarchical distance function. We performed experiments with real and synthetic data. The prop...

• Type: Conference
• Year: 2005
• Where: ICDE
• Authors: Vasileios Megalooikonomou, Qiang Wang, Guo Li, Christos Faloutsos
• Keywords: Database, Distance Function, ICDE 2005, Multi-resolution/hierarchical Distance Function, Original Time Series