Outi Tuisku

Now Dasher! Dash away!: longitudinal study of fast text entry by Eye Gaze

Dasher is one of the best known inventions in the area of text entry in recent years. It can be used with many input devices, but studies on user performance with it are still scarce. We ran a longitudinal study where 12 participants transcribed Finnish text with Dasher in ten 15-minute sessions using a Tobii 1750 eye tracker as a pointing device. The mean text entry rate was 2.5 wpm during the first session and 17.3 wpm during the tenth session. Our results show that very high text entry rates can be achieved with eye-operated Dasher, but only after several hours of training.

A Wearable, Wireless Gaze Tracker with Integrated Selection Command Source for Human‐Computer Interaction

A light-weight, wearable, wireless gaze tracker with integrated selection command source for human-computer interaction is introduced. The prototype system combines head-mounted, video-based gaze tracking with capacitive facial movement detection that enable multimodal interaction by gaze pointing and making selections with facial gestures. The system is targeted mainly to disabled people with limited mobility over their hands. The hardware was made wireless to remove the need to take off the device when moving away from the computer, and to allow future use in more mobile contexts. The algorithms responsible for determining the eye and head orientations to map gaze direction to on-screen coordinates are presented together with the one to detect movements from the measured capacitance signal. Point-and-click experiments were conducted to assess the performance of the multimodal system. The results show decent performance in laboratory and office conditions. The overall point-and-click accuracy in the multimodal experiments is comparable to the errors in previous research on head-mounted, single modality gaze tracking that does not compensate for changes in head orientation.

The effect of clicking by smiling on the accuracy of head-mounted gaze tracking

The effect of facial behaviour on gaze tracking accuracy was studied while using a prototype system that integrated head-mounted, video-based gaze tracking and a capacitive facial movement detection for respective pointing and selecting objects in a simple graphical user interface. Experiments were carried out to determine how voluntary smiling movements that were used to indicate clicks affect the accuracy of gaze tracking due to the combination of user eye movement behaviour and the operation of gaze tracking algorithms. The results showed no observable degradation of the gaze tracking accuracy when using voluntary smiling for object selections.

Text entry by gazing and smiling

Face Interface is a wearable prototype that combines the use of voluntary gaze direction and facial activations, for pointing and selecting objects on a computer screen, respectively. The aim was to investigate the functionality of the prototype for entering text. First, three on-screen keyboard layout designs were developed and tested (n = 10) to find a layout that would be more suitable for text entry with the prototype than traditional QWERTY layout. The task was to enter one word ten times with each of the layouts by pointing letters with gaze and select them by smiling. Subjective ratings showed that a layout with large keys on the edge and small keys near the center of the keyboard was rated as the most enjoyable, clearest, and most functional. Second, using this layout, the aim of the second experiment (n = 12) was to compare entering text with Face Interface to entering text with mouse. The results showed that text entry rate for Face Interface was 20 characters per minute (cpm) and 27 cpm for the mouse. For Face Interface, keystrokes per character (KSPC) value was 1.1 and minimum string distance (MSD) error rate was 0.12. These values compare especially well with other similar techniques.

Longitudinal study on text entry by gazing and smiling

This study presents the results of a longitudinal study on multimodal text entry where objects were selected by gazing and smiling. Gaze was used to point at the desired characters and smiling movements were performed to select them. Participants (N=12) took part in the experiments where they entered text for a total of 2.5 hours in ten 15-minute-long sessions during one-month time period. The results showed that the text entry rate improved with practice from 4.1 to 6.7 words per minute. However, the learning curve had not reached its plateau phase at the end of the experiment. Subjective ratings showed that the participants appreciated this multimodal technique.

Gaze and head pointing for hands-free text entry: applicability to ultra-small virtual keyboards

With the proliferation of small-screen computing devices, there has been a continuous trend in reducing the size of interface elements. In virtual keyboards, this allows for more characters in a layout and additional function widgets. However, vision-based interfaces (VBIs) have only been investigated with large (e.g., full-screen) keyboards. To understand how key size reduction affects the accuracy and speed performance of text entry VBIs, we evaluated gaze-controlled VBI (g-VBI) and head-controlled VBI (h-VBI) with unconventionally small (0.4°, 0.6°, 0.8° and 1°) keys. Novices (N = 26) yielded significantly more accurate and fast text production with h-VBI than with g-VBI, while the performance of experts (N = 12) for both VBIs was nearly equal when a 0.8--1° key size was used. We discuss advantages and limitations of the VBIs for typing with ultra-small keyboards and emphasize relevant factors for designing such systems.

Smile to save it: facial expressions for lifelogging

Current aim was to introduce and initially evaluate the performance of a system called Extended Cognition, which was developed for enhancing the filtering of emotionally meaningful information from visual lifelogging data. The system is proposed to add facial expression markers to the stream of visual lifelogging data in order to later find special, possibly emotionally meaningful moments from the data. In an initial user study we collected subjective evaluations (N=10) about the ergonomics of the data measurement setup and the use of voluntary smiles and frowns for adding markers. Experience evaluations about the system were also collected. Results showed that data measurement setup was ergonomic to use and the system was evaluated positively. Smiling was rated as pleasant, natural, and functional expression for data marking purposes. Participants considered that, for example, the system would support memorization, and that it could be used to share important memories with others.

Effects of Electronic Word-of-Mouth on the Potential Customer's Emotions and Product Image

Thisstudyinvestigatedhowpotentialcustomers(N=28)respondtotwotypesofelectronicwordof-mouth(eWOM)regardingthesameproduct.Thestudysimulatedrealitybyhavingparticipants readeithermainlynegativecommentsfromanindependentdiscussionforum(n=14)ormainly positivecommentsfromamarketer’swebsite(n=14).Theresultsshowedthattheparticipants’valence ratings were positive after reading eWOM on the marketer’s website and negative after reading eWOMontheindependentforum.Althoughthisseemsobvious,itisinterestingthateventhough thecommentsontheindependentforumwerenotconsideredtrustworthyorexpert,readingthese commentsnegativelyinfluencedtheproductimage.Participantswhoreadtheindependentforum ratedtheproductimagesignificantlylowerthanparticipantswhoreadthemarketer’swebsite.After watchingcommercialvideos,bothgroupsratedtheproductimagehigher;however,thedifference betweenthegroupsremainedsignificant.TheresultssuggestthattheemotionsevokedbyeWOM playakeyroleinproductimage.Apracticalimplicationforcompaniesmaybepurchasingtargeted advertisingondiscussionforumstomanagepotentialcustomers’negativeaffectivereactions.