TAUCHI – Tampere Unit for Computer-Human Interaction Manual Text Entry: Experiments, Models, and Systems Poika Isokoski Tampere Unit for Computer-Human Interaction Department of Computer Sciences University of Tampere, Finland

TAUCHI – Tampere Unit for Computer-Human Interaction Writing There is no natural way to write. 1

TAUCHI – Tampere Unit for Computer-Human Interaction At School I did not understand why the inferior pen and paper technology was still taught to children. 2

TAUCHI – Tampere Unit for Computer-Human Interaction Multiple writing technologies Pen and paper and computers are used for writing. 3

TAUCHI – Tampere Unit for Computer-Human Interaction Structure of the Work I: Device Independent Text Input: Rationale and an Example II: Comparison of two Toucpad-Based Methods for Numeric Entry III: Evaluation of Multi-device Extension of Quikwriting IV: Performance of Menu-augmented Soft Keyboards VI: Combined Model for Text Entry Rate Development V: Model for Unistroke writing time VII: Architecture for Personal Text Entry Methods 4

TAUCHI – Tampere Unit for Computer-Human Interaction Paper IV: Introduction Performance of Menu-Augmented Soft Keyboards Video 5

TAUCHI – Tampere Unit for Computer-Human Interaction Paper IV: Model Simulator: –Fitts’ law for pointing ( t = a + b log(A/W+1) ). –Constant 160 ms for selection (McQueen et al., GI 1995). –Given a text string the simulator computes how long entering it takes. Used the 500 phrase set published by MacKenzie and Soukoreff (CHI2003). demo 6

TAUCHI – Tampere Unit for Computer-Human Interaction Paper IV: Model: results QWERTY: 26% faster 7

TAUCHI – Tampere Unit for Computer-Human Interaction Paper IV: Model: discussion 1 Why does it seem to be faster? Because it saves stylus travel: –Without menu: –With menu: 8

TAUCHI – Tampere Unit for Computer-Human Interaction Paper IV: Model: discussion 2 Is the model realistic and reliable? –Maybe. –It could reflect user’s motor performance fairly accurately. –It does not know anything about cognitive factors.  Experiments are needed. 9

TAUCHI – Tampere Unit for Computer-Human Interaction Paper IV: Experiment I: task Measured the motor performance. –12 participants entered repeating patterns: 10

TAUCHI – Tampere Unit for Computer-Human Interaction Paper IV: Experiment I: results When the patterns are simple (left), using the menu is faster When the patterns are more complex (right), the difference is smaller 11

TAUCHI – Tampere Unit for Computer-Human Interaction Paper IV: Experiment I: discussion Atomic menu selection is faster than pointing (on average). Deciding whether to point or select takes time. It could be that in real writing situation the cognitive planning dominates making using the menu slower than not using it.  Another experiment was needed. 12

TAUCHI – Tampere Unit for Computer-Human Interaction Paper IV: Experiment II: task Text transcription task: –The same software –6 participants –20 sessions (15 min with the menu and 15 min without it per session) –The menu was optimized based on the results of Experiment I 13

TAUCHI – Tampere Unit for Computer-Human Interaction Paper IV: Experiment II: results Text entry rate: 14

TAUCHI – Tampere Unit for Computer-Human Interaction Paper IV: Conclusions Using the menu may allow faster text entry rates, but –only after a lot of training (>>5 hours) –at the cost of added cognitive load –the increase in text entry rate may not be that great (model says max 26%). The menu does not disturb those users who do not want to use it. 15

TAUCHI – Tampere Unit for Computer-Human Interaction Summary The thesis contributes in four ways: –Device independent text entry –Data on text entry method performance –Models of user performance –A software architecture for text entry 16