We describe a novel technique to provide semi-private feedback on a shared public screen. The technique uses a no-onset presentation that takes advantage of perceptual limitations in human vision to avoid alerting other users to feedback directed at one individual user by suppressing the sudden onset of the feedback. Three experiments evaluated the effectiveness of the technique and appropriate timing parameters and alternatives for presentation onset. Our experiments indicated that an 80 ms no-onset presentation allows participants to interpret information directed to them with over 90% accuracy, but their ability to interpret simultaneously presented information intended for others will be close to random chance. The technique initially camouflages the information being presented by overlaying additional visual elements and then removes those elements to reveal only the elements encoding the information being presented. We discuss applications for the technique, including classroom clicker usage, which was our original motivation for the study.

中文翻译：

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通过控制演示开始在共享的公共屏幕上提供半私密的反馈

我们描述了一种在共享公共屏幕上提供半私人反馈的新技术。该技术使用无开始演示，利用人类视觉的感知限制，通过抑制反馈的突然出现来避免提醒其他用户针对单个用户的反馈。三个实验评估了该技术的有效性以及适当的时间参数和演示开始的替代方案。我们的实验表明，80 毫秒的无开始演示允许参与者以超过 90% 的准确度解释指向他们的信息，但他们解释同时呈现给他人的信息的能力将接近随机机会。该技术最初通过覆盖额外的视觉元素来伪装所呈现的信息，然后移除这些元素以仅显示编码所呈现信息的元素。我们讨论了该技术的应用，包括课堂答题器的使用，这是我们研究的最初动机。