%0 Journal Article %T Online Strategy Clustering Based on Action Sequences in RoboCupSoccer Small Size League %J Robotics | An Open Access Journal from MDPI %D 2019 %R https://doi.org/10.3390/robotics8030058 %X This paper addresses a strategy learning problem in the RoboCupSoccer Small Size League (SSL). We propose a novel method based on action sequences to cluster an opponent¡¯s strategies online. Our proposed method is composed of the following three steps: (1) extracting typical actions from geometric data to make action sequences, (2) calculating the dissimilarity of the sequences, and (3) clustering the sequences by using the dissimilarity. This method can reduce the amount of data used in the clustering process; handling action sequences instead of geometric data as data-set makes it easier to search actions. As a result, the proposed clustering method is online feasible and also is applicable to countering an opponent¡¯s strategy. The effectiveness of the proposed method was validated by experimental results. View Full-Tex %U https://www.mdpi.com/2218-6581/8/3/58