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Designing a Hybrid Layout for a Five-Key Text Entry Technique

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Five-key text entry methods are useful for limited text entry on small devices. They use four directional keys to move a selector over an on-screen keyboard and an Enter key for selection. Although other researchers have described five-key character layouts using alphabetical order and predictive layouts based on digraph frequencies, there is considerable latitude in designing the rest of a comprehensive on-screen keyboard. Furthermore, it might be possible to capitalize on the relative strengths of the alphabetic and predictive layouts by combining them in a hybrid layout. In this paper, we describe the design factors considered and tools used to develop three five-key text-entry techniques: alphabetic, predictive, and hybrid.
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... The layouts are stored in an xml file, and it is possible to change the layout as a function of the last character typed. This feature permits the implementation of predictive keyboards based on digraph frequencies (as in Bellman & MacKenzie, 1998;MacKenzie, 2002b;Millet, Asfour, & Lewis, 2008). The tool also supports the display of keyboard layouts across n rows, where n is a user-specified attribute. ...
... Different cursor positioning and movement techniques can affect the ease and efficiency of selection-based text entry (Millet et al., 2008), so researchers can enable or disable these features. Cursor positioning can be persistent or snap-to-home. ...
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