Transformation of Variant-Length Time Series based on Dynamic Time Warping for Effective Classification
Hwanchul Lee, Sun Hur · Journal of Korean Institute of Industrial Engineers · 2020
Time series data produced from various sensors are mostly different from each other in length due to various environment of collection. Most time series classification methods, however, assume that the lengths of time series data are the same. There is no alternative, moreover, for variant-length time series classification except DTW and DTW-related methods and few researches on transformation of time series length can be found in direct ways. In this paper, we propose a length transformation method for effective variant-length time series classification. Proposed method is a similarity-preserving transformation and the restoration is possible. To evaluate the proposed method, experiments are conducted to compare the classification performance by applying well-known methods to the time series data before and after the transformation. The classification using the dataset transformed by the proposed method shows better performance on almost all measurements.