1. Fall 2002CS/PSY 67501 Dialog Design 3 How to use a PDA

2. Fall 2002CS/PSY 67502 Personal Digital Asst. (PDA) Palm VII HP Jornada Handspring Visor Palm IIIc Apple Newton (1993)

3. Fall 2002CS/PSY 67503 PDAs Becoming more common and widely used Smaller display (160x160), (320x240) Few buttons, interact through pen Estimate: 14 million shipped by 2004 Improvements  Wireless, color, more memory, better CPU, better OS Palmtop versus Handheld

4. Fall 2002CS/PSY 67504 No Shredder…

5. Fall 2002CS/PSY 67505 Input Pen is dominant form Three main techniques  Free-form ink  Soft keyboards (tapping)  Recognition systems Also can connect keyboard

6. Fall 2002CS/PSY 67506 Free-form Ink Ink is the data, take as is Human is responsible for understanding and interpretation Like a sketch pad Example Digital Ink - CMU  video, CHI ‘98 Flatland - Xerox PARC  video, CHI ‘99

7. Fall 2002CS/PSY 67507 Soft Keyboards Common on PDAs and mobile devices Many varieties  Tapping interface  Stroking interface

8. Fall 2002CS/PSY 67508 Tapping Interface Presents a small diagram of keyboard You click on buttons/keys with pen QWERTY vs. alphabetical  Tradeoffs?  Alternatives?

9. Fall 2002CS/PSY 67509 Tegic Communications-T9 Tapping interface that uses phone pad You press out letters of your word, it matches the most likely word, then gives optional choices Used in mobile phones www.tegic.com/t9

10. Fall 2002CS/PSY 675010 Cirrin Developed by Jen Mankoff (GT->Cal) Word-level unistroke technique

11. Fall 2002CS/PSY 675011 Recognition Systems Recognizing letters and numbers Special symbols Handwriting Recognition Lots of systems (commercial too) English, kanji, etc. Not perfect, but people aren’t either!  People - 96% handprinted single characters  Computer - >97% is really good OCR (Optical Character Recognition)

12. Fall 2002CS/PSY 675012 Recognition Issues Off-line vs. On-line  Off-line: After all writing is done, speed not an issue, only quality  On-line: Must respond in real-time Bitmapped vs. Vectorized  Bitmapped: Usually off-line, like OCR  Vectorized: On-line, uses angle, direction, speed, pressure, acceleration, etc.

13. Fall 2002CS/PSY 675013 More Issues Boxed vs. Free-Form input  Sometimes encounter boxes on forms Printed vs. Cursive  Cursive is much more difficult Letters vs. Words  Cursive is easier to do words Using context & words can help  Usually requires existence of a dictionary  Check to see if word exists  Consider 1/I/l Training - Many systems improve a lot with training data

14. Fall 2002CS/PSY 675014 Special Alphabets Graffiti - Unistroke alphabet on Palm PDA  Experience? Other alphabets or purposes  Gestures for commands

15. Fall 2002CS/PSY 675015 Pen Gesture Commands - Might mean delete Define a series of (hopefully) simple drawing gestures that mean different commands in a system

16. Fall 2002CS/PSY 675016 Pen Use Modes Often, want a mix of free-form drawing and special commands  Might use visible mode switch  Might have pen action buttons/switches

17. Fall 2002CS/PSY 675017 Error Correction Having to correct errors can slow input tremendously Strategies  Erase and try again  n-best list ...

18. Fall 2002CS/PSY 675018 Interesting Applications Signature verification Note-taking  Academic course  Corporate meeting Sketching systems  Designers’ aids Example Silk - J. Landay, CMU  Video, CHI ‘96