The paper challenges the notion that any Fitts' Law model can be applied generally to human-computer interaction, and proposes instead that applying Fitts' Law requires knowledge of the users' sequence of movements, direction of movement, and typical movement amplitudes as well as target sizes. Two experiments examined a text selection task with sequences of controlled movements (point-click and point-drag). For the point-click sequence, a Fitts' Law model that used the diagonal across the text object in the direction of pointing (rather than the horizontal extent of the text object) as the target size provided the best fit for the pointing time data, whereas for the point-drag sequence, a Fitts' Law model that used the vertical size of the text object as the target size gave the best fit. Dragging times were fitted well by Fitts' Law models that used either the vertical or horizontal size of the terminal character in the text object. Additional results of note were that pointing in the point-click sequence was consistently faster than in the point-drag sequence, and that pointing in either sequence was consistently faster than dragging. The discussion centres around the need to define task characteristics before applying Fitts' Law to an interface design or analysis, analyses of pointing and of dragging, and implications for interface design.

中文翻译：

---

菲茨定律应如何应用于人机交互？

本文对任何菲茨定律模型都可以普遍应用于人机交互的概念提出了挑战，并提出，应用菲茨定律需要了解用户的运动顺序，运动方向，典型运动幅度以及目标尺寸。有两个实验检查了文本选择任务，并控制了运动的顺序（单击鼠标和拖动鼠标）。对于点击点序列，采用菲茨定律模型，该模型以指向方向（而不是文本对象的水平范围）为目标，使用跨文本对象的对角线作为目标大小，从而为指向时间数据提供了最佳拟合，而对于点拖动序列，使用文本对象的垂直大小作为目标大小的菲茨定律模型可以提供最佳拟合。Fitts定律模型很好地拟合了拖动时间，该模型使用了文本对象中终端字符的垂直或水平尺寸。需要注意的其他结果是，单击点单击序列中的指针始终比点拖动序列中的指针更快，并且任一序列中的指针始终比拖动过程更快。讨论围绕在将“菲茨定律”应用于界面设计或分析，指向和拖动的分析以及对界面设计的含义之前定义任务特征的需求。而且无论用哪种顺序指向，始终比拖动要快。讨论主要围绕在将Fitts定律应用于界面设计或分析，指向和拖动的分析以及对界面设计的含义之前定义任务特征的需求。而且无论用哪种顺序指向，始终比拖动要快。讨论围绕在将“菲茨定律”应用于界面设计或分析，指向和拖动的分析以及对界面设计的含义之前定义任务特征的需求。