This is the presentation of my graduation thesis that I have written after a long term of research and development, followed by experiments and analyses. In this project, I have proposed a dynamic method to typing and a design to be used with Eye Trackers. The designs were tested in experiments with 13 participants. Results are available in the presentation. The proposed methods eased and accelerated the typing with Eye Trackers

1. DYNAMIC, ADAPTIVE AND
PERSONALIZED USER INTERFACE FOR
COMMUNICATION USING EYE TRACKERS
KADIR AKDENIZ
040070204
ASSOC. PROF. ZEHRA ÇATALTEPE
12.06.2014

2. CONTENTS
• Motivation
• Purpose & Hypotheses
• Basic Design
• First Proposal: Dynamic Approach to Typing
• Transition Probabilities
• Second Proposal: Circular Design for Eye
Trackers
• Experiment Setup
• Results
• Discussion
• Conclusion
• Further Work
• Thanks
• References
2

3. MOTIVATION
• The patients who suffer Locked-in Syndrome are unable to speak and thus
communication is a big issue for them to express their needs, feelings, and thoughts.
• The only organs they can still use, are their eyes in most cases.
• They can move their eyes horizontally and vertically.
• This provides a primitive yet promising way of communication.
• When asked a yes or no question, they can say yes by looking up or no by looking
down.
• Likewise, a group of items or words/letters can be shown on a paper or cardboard and
they can choose one or write a word and sentence later
• This is how Eye Trackers work as well.
3

4. PURPOSE & HYPOTHESES
• This study aims to improve their typing by providing a dynamic approach to
typing and also a new design that best suits the nature of Eye Trackers.
• The Dynamic approach simply suggests letters when a letter is typed.
• New Circular Design considers the nature of Eye Trackers and provides a
smoother way by both removing the clicking and avoiding mistyping.
• Without clicking and making less mistakes, it is aimed for the patients to get tired
less quickly and thus write for longer sessions, expressing themselves better.
• Hypotheses are:
• Dynamic approach is expected to be faster than traditional method.
• Circular Design is expected to avoid mistypes.
• Circular Design is expected to be less tiring.
4

5. BASIC DESIGN
• Two State Design
• Space and Delete only
• Both Turkish and English
letters
• This represents the
interfaces with big and
few buttons that are used
in the field.
• The user has to blink
his/her eyes to generate a
left-click
5

6. RECTANGULAR
STATIC
• Basic Design
6

7. FIRST PROPOSAL: DYNAMIC METHOD
• N-State Design
• After a letter is typed, five
letters are suggested.
• Next five letters are also
provided.
• User can cycle through all
letters.
• Back button is used to
escape to initial state
[shortcut].
• The user has to blink
his/her eyes to generate a
left-click.
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8. TRANSITION PROBABILITIES
• The letters are suggested based on their
frequencies, probabilities.
• The frequencies of letters, before and after
each letter.
• More sensitive results were needed for the
missing letters.
• Transition probabilities were gathered
from electronic versions of about 10
selected books, written in Turkish.
• The results are consistent with that of
Dalkılıç and Dalkılıç [1].
• The table is retrieved from: [1] Dalkiliç, M. E., & Dalkiliç, G. (2002). On the cryptographic patterns and frequencies in Turkish language. In Advances in
Information Systems (pp. 144-153). Springer Berlin Heidelberg 8

9. RECTANGULAR
DYNAMIC
• Dynamic Method
9

10. SECOND PROPOSAL: CIRCULAR DESIGN
• This design also has Static
and Dynamic versions.
• Circular tries to avoid
mistakes/mistypes.
• It does not require click.
• Secondary (red) cursor
does the click instead.
10

11. CIRCULAR STATIC
• Static version
11

12. CIRCULAR
DYNAMIC
• Dynamic version
12

13. EXPERIMENT SETUP
• 10 most frequently used words in
Turkish[2].
• The order of the words are randomized for
each experiment.
• The order of the designs to be tested are
randomized.
• 13 people participated in 16 experiments.
3 of the participants did the experiments
twice.
• Most frequent words:
• Bir, Bu, Ben
• Demek, Çok, Yapmak
• İçin, Ve, Ne, Olmak
• [2] : Wiktionary Project. Word Frequency List, Turkish. Retrieved from http://en.wiktionary.org/wiki/Wiktionary:Frequency_lists/Turkish on June 4th,
2014. 13

14. EXPERIMENT SETUP
• The experiments are done in Pretest –
Posttest fashion.
• In both pretests and posttests, basic
movement times are gathered.
• These base values are subtracted from
actual times in order to find Search Times.
• Participants are asked to fill a survey
before the experiment regarding their
physical conditions.
• The survey of each design was filled by the
participant right after the testing of design.
14

15. RESULTS
• Duration
Designs Numerical
Results
Meaning F-value P-value F-criteria
Rectangular Static 171.63 sec Base method
Rectangular Dynamic 161.79 sec Slightly Faster (6%) 0.87 0.38 4.17
Circular Static 221.48 sec Base method
Circular Dynamic 178.33 sec Significantly Faster (24%) 15.59 0.44 x 10-3 4.17
• Circular Design avoids mistakes => multiply effect on dynamic method.
• Circular Design has a base time of 1.5 sec to reach its destination for the secondary
(red) cursor on the screen.
15

16. RESULTS
• Speed: Interaction / Successful Character Typed
Designs Numerical Results Meaning F-value P-value F-criteria
Rectangular Static 2.07 Base method
Rectangular Dynamic 1.69 23% less interactions
per character
17.00 0.27 x 10-3 4.17
Circular Static 2.13 Base method
Circular Dynamic 1.74 22% less interactions
per character
39.58 0.62 x 10-6 4.17
16

17. RESULTS
• Speed: Successful Character Typed / Minute.
Designs Numerical Results Meaning F-value P-value F-criteria
Rectangular Static 16.34 Base method
Rectangular
Dynamic
17.59 8% increase in speed 1.47 0.24 4.17
Circular Static 12.39 Base method
Circular Dynamic 15.70 27% increase in speed 19.37 0.13 x 10-3 4.17
• Circular Design avoids mistakes => multiply effect on dynamic method.
• Circular Design has a base time of 1.5 sec to reach its destination for the secondary
(red) cursor on the screen.
17

18. RESULTS
• Tiredness : « This design was tiring. »
Designs Numerical Results The Meaning F-value P-value F-criteria
Rectangular Static 0.31 A Bit Tiring
Circular Static -0.81 Not Tiring 8.47 0.68 x 10-2 4.17
Rectangular Dynamic 0 Mediocre
Circular Dynamic -1 Not Tiring 10 0.36 x 10-2 4.17
The Likert Scale
2 1 0 -1 -2
Strongly agree Agree Neither agree
nor disagree
Disagree Strongly Disagree
18

19. RESULTS
• Deletion Percentage (%)
Designs Numerical
Results
The Meaning F-value P-value F-criteria
Rectangular Static 0.59 x 10-1 Base design
Circular Static 0.18 x 10-1 70% decrease in mistakes 8.63 0.63 x 10-2 4.17
Rectangular Dynamic 0.68 x 10-1 Base Design
Circular Dynamic 0.21 x 10-1 70% decrease in mistakes 11.75 0.18 x 10-2 4.17
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20. RESULTS
• Participants with two experiments.
• Rectangular Static
Variable #6 #7 #8
Duration 189 sec 166 sec 141 sec 164 sec 182 sec 147 sec
Inter/Char 2.34 2.29 1.88 1.93 1.88 2.02
Char/Min 14.54 15.89 19.05 17.51 14.47 19.01
Deletion % 0.1 0.1 0.02 0.05 0.02 0.08
Variable #6 #7 #8
Duration 133 sec 142 sec 143 sec 145 sec 141 sec 143 sec
Inter/Char 1.57 1.68 1.45 1.44 1.35 1.8
Char/Min 20.17 18.95 19.18 20.26 19.02 18.82
Deletion % 0.04 0,05 0.02 003 0 0.07
• Rectangular Dynamic
20

21. RESULTS
• Participants with two experiments.
• Circular Static
Variable #6 #7 #8
Duration 217 sec 196 sec 208 sec 240 sec 255 sec 193 sec
Inter/Char 2.08 2 2 2.26 2.24 2
Char/Min 12.4 13.7 12.97 11.48 10.55 13.96
Deletion % 0 0 0 0.04 0.04 0
Variable #6 #7 #8
Duration 150 sec 170 sec 164 sec 152 sec 169 sec 141 sec
Inter/Char 1.57 1.69 1.58 1.57 1.76 1.57
Char/Min 17.96 16.17 16.75 17.65 16.29 19.01
Deletion % 0 0 0 0 0.04 0
• Circular Dynamic
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22. RESULTS
• Search Time Analysis
• The mean value for Static
Rectangular is always lower
than Dynamic.
• Two dynamic mechanisms in
Dynamic version cause this:
• Transition Probabilities
• Redistribution of next letters
-2000
-1000
0
1000
2000
3000
4000
0 10 20 30 40 50 60 70 80 90 100
34: Static, Avg: 213.06 ms
İÇİN_NE_BEN_ÇOK_YAPMAK_DEMEK_BİR_VE_BU_OLMAK_
-2000
-1000
0
1000
2000
3000
4000
5000
0 10 20 30 40 50 60 70 80
36: Dynamic, Avg: 479.74 ms
BU_ÇOK_DEMEK_YAPMAK_BİR_İÇİN_OLMAK_VE_BEN_NE_
22

23. RESULTS
• Eye Movement Analysis
Movement Directions Average Values
Rightward – short 1.57 sec
Leftward – short 1.86 sec
Upward 1.77 sec
Downward 1.43 sec
Movement Directions Average Values
Right-Down short 1.56 sec
Left-Down short 1.37 sec
Left-Up short 1.56 sec
Right-Up short 1.52 sec
Right-Down long 1.49 sec
Left-Down long 1.36 sec
Left-Up long 1.53 sec
Right-Up long 1.59 sec
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24. CONCLUSION
• In this study, a new dynamic method is proposed in order to improve typing with
Eye Trackers for interfaces with big and few buttons; as well as a new Circular
design that suits the Eye Trackers.
• Dynamic method suggests letters in order to increase speed while typing.
• Circular Design does the click for the user and also avoids the mistypes as much as it
can. This provides a less tiring method for the users, so they can write for much
longer and express themselves much better.
• The Dynamic method achieves a slight increase in Rectangular Design and a
significant increase in Circular Design with the help of avoiding mistakes.
• Circular design achieves to decrease the deletion percentage by 70% and is
considered the least tiring design by the participants.
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25. DISCUSSION
• How are these methods and designs adaptive?
• How are these methods and designs dynamic?
• How are these methods and designs personalized?
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26. FURTHER WORK
• In this study, the proposed methods and designs were tested in order to observe
whether the changes had any effect.
• For further works, the functionality of the designs can be improved in such ways
that:
• The users can have options to change the screen into a menu or other possible sets
of characters or numbers.
• The users can have more than look and click abilities with off-screen targets or any
other means, in order to improve their command on the computers or softwares [3].
• The users can be provided with different sets of transition probabilities in order to
use the proposed designs for different purposes such as writing in a different
language or a programming language (C++, Python, etc.).
• The proposed designs and methods can be implemented in a software with other
features that allow operations such as e-mail, browser, media players and more.
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27. THANKS
• I would like to thank
• Assoc. Prof. Zehra Çataltepe for her invaluable contributions and guidance throughout this
study,
• Technical University of Istanbul and Faculty of Computer & Informatics for their assistance
on accessing the required devices in Usability Laboratory,
• Müge Erel, Gözde Gül İşgüder and Ahmet Arış for their valuable assistance in Usability
Laboratory,
• Muhsin Doğrular and Cüneyt Özveren for sharing their experiences on Eye Trackers and
assistances on building up the definition of this study,
• And all the participants for making the experiments possible.
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28. REFERENCES
• [1] Dalkiliç, M. E., & Dalkiliç, G. (2002). On the cryptographic patterns and
frequencies in Turkish language. In Advances in Information Systems (pp. 144-
153). Springer Berlin Heidelberg.
• [2] Wiktionary Project. Word Frequency List, Turkish. Retrieved from
http://en.wiktionary.org/wiki/Wiktionary:Frequency_lists/Turkish on June 4th,
2014.
• [3] Isokoski, P. (2000, November). Text input methods for eye trackers using
off-screen targets. In Proceedings of the 2000 symposium on Eye tracking research
& applications (pp. 15-21). ACM
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29. THANK YOU.
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