Individual diVerences in tracking

The present experiment compared diVerences in response strategy of participants performing a two-dimensional tracking task at three diVerent levels of task diÅculty. Twelve participants tracked an iconic aeroplane target as accurately as possible for nine repeated trials each of 5 min duration. The random input and individual response output were calculated in terms of direction and velocity. Speci®cally, for each 200-ms sample period, a calculated combination of eight trajectories and three velocities provided a 24 combinatorial description of both random input and participant response. Distributions across these combinations represent descriptive results and re¯ect individual characteristics. The distribu-tions were compared using the technique of correspondence factor analysis. The outcome of this multidimensional method was that ®rst, between-participants discrimination was best served by the up-vertical and low-velocity combination and, second, that the former pattern typi®ed poor performers, while more skilled individuals used all directional options at the highest velocity level. Implications for individualized controls are examined. 1