Visualization of baseball player´s defensive range using a probability ellipse

In this study, we propose a way to evaluate and visualize defensive ability for baseball players. Fielding average is famous for an index of the defense, but thinks about other evaluation methods. We visualize the defensive range of players with the positions of batted ball processing. We will see that player is going to challenge the batted ball which cannot catch by visualizing. We did an ellipse estimate using a variance-covariance matrix for the visualization of the defensive range. The probability ellipse expresses the virtual defensive range of the player. We can assume the area of this defensive range an index. Because we might leave batted ball processing to other players, we established the border between players. We will understand the activity of the player on this border. We can think about the good or bad of the player by thinking about an ellipse estimate and a border.