Visualization of dominant region in team games and its application to teamwork analysis

The authors present a method for visualization of an invisible feature in human group motion. This feature called "dominant region" is a kind of dynamic sphere of influence. A dominant region is defined as a region in where the person can arrive earlier than any other persons and can be formulated by replacing the distance function in the Voronoi region with a time function. As an application of the dominant region, a motion analysis system of team ball games was developed. In this system, the dominant region is used for quantitative evaluation of basic teamwork. From the experiments using actual soccer game scenes, it was shown that inferior or superior areas for each player and each team in the game can be observed visually and that some basic factor for teamwork can be evaluated quantitatively by using the dominant region. These evaluation results almost correspond with those by some professionals.