Steering Performance with Error-accepting Delays

In steering law tasks, deviating from the path is immediately considered an error operation. However, in navigating a hierarchical menu item, which is a representative application of the law, a deviation within a short duration is sometimes permitted. We tested the validity of the steering law model with various durations of such error-accepting delays and found that it showed high fits for each delay condition (R^(2) > 0.96) but poor fits if the delay values were not separated (R^(2) = 0.58). Because the average movement speed linearly increased as the delay increased, we refined the model by taking the delay into account, and the fitness was significantly improved (R^(2) = 0.97). Our model will help GUI designers estimate the average operational time on the basis of the menu item length, width, and error-accepting delay.