The impact of candidate display styles for Japanese and Chinese characters on input efficiency

Entering non-alphabetic text for languages such as Japanese and Chinese into a computer typically consists of typing Roman character-based phonemes and selecting the intended Japanese or Chinese character from a list of homophonic candidates. This paper presents a study of four candidate display styles. Three of them, Vertical, Horizontal, and Compact-Horizontal, are used in commercial products. The fourth style, Matrix, is novel. The candidate display style is studied in conjunction with various manual selection devices including Mouse, Numeric Keys, Spacebar, Cursor Key, and Numeric Keypad. Results show that a great deal of time is taken to choose the correct character in both Chinese and Japanese input. The candidate display style affects both input efficiency and subjective preference. Results also show that the Compact-Horizontal display style outperforms other display styles with a normal keyboard but the Matrix display style is the most efficient when used with a Numeric Keypad due to stimulus–response compatibility and the movement efficiency of such a design.