The Effect of Feedback on Chord Typing

The amount of visual feedback when using a mobile device in a busy context is often limited. For example, while texting and walking in a crowded place, we need to focus on the environment and not on the phone. A way to type fast, accurately and with limited visual feedback is represented by chording keyboards. We present a study on such a chording keyboard prototype and analyze the influence of having visual, audio or no feedback at all on the typing process. The typing rates are the same under all three conditions, with an average of 20 words per minute, after approximately 350 minutes of practice. The average error rates are the lowest in the absence of feedback (2.41%) and the highest when the users can see what has been typed (4.03%). Considering these results, the proposed text input method is a viable option in situations where visual attention is already committed to other tasks. Keywords-chording keyboard; text entry; blind typing; feedback