Beginner Performance with the GKOS Chorded Keyboard

The number of mobile computing devices is increasing at a very fast pace. A large number of today's mobile phones still have 12-key keypads for text entry. However, many of the novel smart phones are equipped with QWERTY keypads or virtual keyboards that provide better performance for text input. This thesis reports a user experiment investigating the early learning phase of a sixkey chorded keyboard method called GKOS. The experiment focused on the following questions: how easy is it to learn the basic key combinations of GKOS in order to type full sentences, how rapidly does GKOS typing speed increase in the early phase of learning, how does GKOS compare to the other common mobile text entry methods in terms of typing speed, and what kind of reception does the GKOS method get from mobile users with alternating experience of mobile text entry systems? QWERTY keyboards were modified as test devices, and two software applications were set up for the thesis' purposes. The user experiment consisted of a text entry pre-test phase, an eight-day GKOS learning phase, as well as a pre-experiment and a post-experiment questionnaire. The major findings from the user experiment were positive. The users were able to quickly comprehend and learn the GKOS character map. The development of text entry skill was encouraging: there was a lot of diversity among the participants, but they had an overall improvement of 277% between the first and last phrase set. After a short learning phase, participants' mean GKOS text entry speed surpassed the mean multi-tap text entry speed. Based on the experiment results, we suggest GKOS to be further studied in the form of a longitudinal study and with test devices that better resemble the GKOS concept devices designed by the creator of GKOS. The GKOS method is unlikely to become a successful competitor for QWERTY keypad and virtual keyboard in the mobile phone market in the coming years. However, the method might have potential in device categories and situations, where hunt-and-peck typing is not an option. For instance, in-vehicle infotainment systems (IVIS) could benefit from a GKOS implementation. Asiasanat:text entry, chorded keyboard, GKO