Symbol Creator

Usability evaluation of a novel pen-based text input technique

Melinda LuomaNew Interaction Techniques

February 25, 2003

Introduction to the Problem

Lot of time spent writing SMSs - how about faster text entry?

Smaller keyboards needed for smaller devices

TEXT MESSAGING GROWTH (SMS)UK GSM NETWORK OPERATOR TOTALS

June 1998 - October 2002

http://www.mda-mobiledata.org/resource/hottopics/smssept.asp

Previous Research

Symbol Creator = assembling characters using symbols that resemble basic elements of Latin cursive

Two competing paradigms for mobile text entry: – pen-based input vs keyboard-based input

Most work has focused on expert performance; however, novice performance and experience is much more important (MacKenzie, 2002)

Objectives in General

The project aims to carry out a comparative research of two pen-based text input techniques: Symbol Creator and multi-tap– speed, accuracy, subjective experiences

– learning

In particular, to measure novice performance – problems: novice with SC, but not multi-tap;

where to find novice subjects in both methods?

Schedule

Week Activity Results8 testing data9 testing data10 data analysis statistical data11 data analysis statistical data12 project report paper, draft13 project report paper, draft14 report ready paper, final

Research Methods

Overview to introduction to the field of pen-based text entry techniques

Empirical research based on earlier research on novel pen-based text entry techniques

Experiment Design

Settings PhEntry SCEntry

Subjects 8 novice 8 novice

Words 20 20

Trials 7 7

Practice 5 min 15 min

Experimental Setup (1)

PDA Jornada Tauchi laboratory PhEntry software by Grigori Text entry parameters and user performance

– speed = wpm– accuracy = errors– keystrokes & time per word– reaction time per character and variations

Experimental Setup (2)

PDA Jornada Tauchi laboratory PhEntry software by Grigori Text entry parameters and user performance

– speed = wpm– accuracy = errors– keystrokes & time per word– reaction time per character and variations

Preliminary Results (1)

With these subjects, SC demanded more clicks per word than multi-tap

Why?– novice status with SC– learning would

probably decrease the differences between the methods

Clicks per word

0

5

10

15

20

25

30

35

40

45

50

1 2 3

Subject

Aver

age

num

ber o

f clic

ks

multi-tap

SymbolCreator

Preliminary Results (2)

text entry speed

0

5

10

15

20

25

1 2 3 4 5 6 7

trials

seco

nds /

wor

d multi-tap

SymbolCreator

Text entry speed measured by seconds per writing one word– faster with multi-tap

Learning in both methods

Preliminary Results (3)

Reaction times (ms)– shorter with multi-tap

Good learning effect in Symbol Creator

Reaction Times

0

500

1000

1500

2000

2500

1 2 3 4 5 6 7

trials

reac

tion

time multi-tap

SymbolCreator

Preliminary Results (4)

Number of Errors

0

5

10

15

20

25

30

35

40

45

50

1 2 3 4 5 6 7

trials

aver

age

of e

rror

s

multi-tap

SymbolCreator

Number of errors in Symbol Creator decreases fastly

Nearly no errors in multi-tap

Forecasted Results

In a test with novices, multi-tap will probably be faster when measured by reaction times and words per minute

However, learning can be fast measured by reduction of errors and increase of text entry speed

Test method may need some improving: “faster” keyboard for better differentiation of users

Prospective Applications

Handwriting (italic) fonts learning-game for kindergarten

Layout optimization Applications for special needs (cyclic mode, one-

dimensional choice, eye-typing (dwelling time), SC for numerical keyboard (blind manipulations)

Mini-Touchscreen requires mini-keyboard (watches, other mobile…)

References Blickenstorfer, C. H. (1995), Graffiti: Wow!!!! Pen Computing Magazine, January, 30-31.

Brewster, S. (2001), Overcoming the Lack of Screen Space on Mobile Computers. Technical Report TR-2001-87, April. Glasgow University, available at: http://www.dcs.gla.ac.uk/~stephen/papers/tr200187.pdf

Exner, Ch., & Henderson, A. (1995), Cognition and motor skill. In Anne Henderson & Charlane Pehoski (Eds.), Hand function in the child. St. Louis: Mosby-Year Book, pp. 93-110.

Goldberg, D., & Richardson, C. (1993). Touch-typing with a stylus. Proceedings of the ACM Conference on Human Factors in Computing Systems - INTERCHI '93, 80-87. New York: ACM.

Handwriting styles, fontware. Available at: http://www.educationalfontware.com/LG_style.html

Isokoski, P. and Raisamo, R. (2000), Device Independent Text Input: A Rationale and an Example. In V. D. Gesù, S. Levialdi and L. Tarantino (eds.), Proceedings of the Working Conference on Advanced Visual Interfaces AVI 2000, Palermo, Italy, pp. 76-83.

Kirsh D. (1995), Complementary Strategies: Why we use our hands when we think. In Proceedings of the Seventeenth Annual Conference of the Cognitive Science Society. Hillsdale, NJ: Lawrence Erlbaum, available at: http://cogsci.ucsd.edu/~kirsh/Cogsci95/cogsci95.html

MacKenzie, I.S, and Soukoreff, R. W. (2002). Text entry for mobile computing: Models and methods, theory and practice. Human-Computer Interaction. Available at: http://www.yorku.ca/mack/hci3.html

Mankoff, J. and Abowd, G.D. (1998), Cirrin: A word-level unistroke keyboard for pen input. In Proceedings of UIST '98. Technical notes. pp.213-214, available at: http://www.cc.gatech.edu/fce/pendragon/publications/index.html#Cirrin98

Quikwriting. Product information is available at: http://mrl.nyu.edu/projects/quikwriting/

Western script, handwriting styles, available at: http://www.educationalfontware.com/EFI_home_page.html

Zagler, W.I. (2002), Matching Typing Persons and Intelligent Interfaces. In J.Klaus, K.Miesenberger, W. L. Zagler (Eds.), Proceedings of the 8th International Conference on Computers Helping People with Special Needs. ICCHP 2002 Linz, Austria, LNCS Vol. 2398, Springer-Verlag Berlin Heidelberg, pp. 241-242.

Zhai, S., Hunter, M., & Smith, B. A. (2000), The Metropolis keyboard - An exploration of quantitative techniques for virtual keyboard design. Proceedings of the ACM Symposium on User Interface Software and Technology - UIST 2000, New York: ACM, pp. 119-128