Abstract: Using fingers to select small and adjacent targets on direct-touch mobile devices frequently results in erroneous target selections. This paper empirically investigates human performance in target selection task on a direct-touch mobile phone. With respect to one basic target selection technique（Direct Click）, it designs three improved target selection techniques（Shift & Zoom, Tilt, and Drag） and conducts an experiment to evaluate and compare these four techniques. Results reveal that these novel selection techniques are more effective in target selections than traditional selection technique. Detailed analysis further shows the performance and feature of each technique in different conditions. Based on the results of the experiment, this study sheds light on several implications and guidelines in the practical use of each improved selection technique.

Key words: human computer interaction, touch input, interaction technique, target selection, direct input device

摘要： 在直接触摸设备上，利用手指直接点击/选择小目标通常会产生误操作。针对此问题，实证地研究了用户使用不同目标选择技术在移动触摸设备上的性能表现。除了传统的直接点击选择目标技术之外，本研究还设计和实现了三种改进的目标选择技术，分别为：平移放大技术、倾斜技术和吸引技术，而且通过设计实验程序并采集实验数据，评价、对比了四种目标选择技术的性能。研究结果表明三种改进的目标选择技术都比直接点击技术效果好。详细的数据分析进一步阐述了不同目标选择技术的特点和差异。基于实验结果，本研究阐明了改进的目标选择技术在实际应用中的适用场景，以及在用户界面设计中的指导意义。

关键词: 人机交互, 触摸输入, 交互技术, 目标选择, 直接设备