Basic evaluation on soccer inside-kick proficiency

To propose evaluation methodology of proficiency of human actions, we have analyzed soccer inside-kick as the basic stage of research. We analyzed the differences between beginners and experts with appearance-based approach using Dense Trajectories (DT) and clarified valid features in DT to discriminate beginners from experts appropriately. After extraction of features using DT, Principal Component Analysis (PCA) was performed. The first and second-order principal components were adopted to draw a two-dimensional scatter diagram for visualization. HOF and MBHy were selected as effective features compared with HOG and MBHx.