The “crossing time” to pass between objects in lassoing tasks is predicted by Fitts’ law. When an unwanted object, or obstacle , intrudes into the user’s path, users curve the stroke to avoid hitting that obstacle. We empirically show that, in the presence of an obstacle, modified Fitts models for pointing with obstacle avoidance can significantly improve the prediction accuracy of movement time compared with standard Fitts’ law. Yet, we also found that when an object is (only) close to the crossing path, i.e., a distractor , users still curve their stroke, even though the object does not intrude. We tested the effects of distractor proximity and length. While the crossing motion is modified by a nearby distractor, our results also identify that overall its effect on crossing times was small, and thus Fitts’ law can still be applied safely with distractors.

中文翻译：

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必要和不必要的分心避免动作会影响交叉操作中的用户行为

套索任务中物体之间通过的“穿越时间”由菲茨定律预测。当一个不需要的物体，或障碍, 侵入用户的路径，用户弯曲笔划以避免撞到那个障碍物。我们凭经验表明，在存在障碍物的情况下，与标准的 Fitts 定律相比，改进的 Fitts 指向避障模型可以显着提高运动时间的预测精度。然而，我们还发现，当一个物体（仅）靠近交叉路径时，即干扰器，即使对象没有侵入，用户仍然会弯曲他们的笔划。我们测试了干扰物接近度和长度的影响。虽然交叉运动被附近的干扰物修改，但我们的结果还表明，它对穿越时间的总体影响很小，因此菲茨定律仍然可以安全地应用于干扰物。