 The experimental results indicated that features, such as duration of task execution and user head movements, could serve as appropriate indices for skill level evaluation, and provide useful information for integrating various records corresponding to different skill levels and behavioral characteristics.
<clarity>  The experimental results indicated that features, such as duration of task execution and user head movements, could serve as appropriate indices for skill level evaluation, and provide useful information for integrating various records corresponding to different skill levels and behavioral characteristics.
 The experimental results indicated that features, such as duration of task execution and user head movements, could serve as appropriate indices for user skill evaluation, as well as providing valuable clues for revealing personal behavioral characteristics.