| Introduction | | BIB | Full-Text | 1 | |
| Andrew Sears; Vicki Hanson | |||
| Guest Editorial | | BIB | Full-Text | 2 | |
| Shari Trewin | |||
| Evaluation of American Sign Language Generation by Native ASL Signers | | BIBAK | Full-Text | 3 | |
| Matt Huenerfauth; Liming Zhao; Erdan Gu; Jan Allbeck | |||
| There are many important factors in the design of evaluation studies for
systems that generate animations of American Sign Language (ASL) sentences, and
techniques for evaluating natural language generation of written texts are not
easily adapted to ASL. When conducting user-based evaluations, several cultural
and linguistic characteristics of members of the American Deaf community must
be taken into account so as to ensure the accuracy of evaluations involving
these users. This article describes an implementation and user-based evaluation
(by native ASL signers) of a prototype ASL natural language generation system
that produces sentences containing classifier predicates, which are frequent
and complex spatial phenomena that previous ASL generators have not produced.
Native signers preferred the system's output to Signed English animations --
scoring it higher in grammaticality, understandability, and naturalness of
movement. They were also more successful at a comprehension task after viewing
the system's classifier predicate animations. Keywords: American Sign Language, accessibility technology for the deaf, animation,
evaluation, natural language generation | |||
| Goal Crossing with Mice and Trackballs for People with Motor Impairments: Performance, Submovements, and Design Directions | | BIBAK | Full-Text | 4 | |
| Jacob O. Wobbrock; Krzysztof Z. Gajos | |||
| Prior research shows that people with motor impairments face considerable
challenges when using conventional mice and trackballs. One challenge is
positioning the mouse cursor within confined target areas; another is executing
a precise click without slipping. These problems can make mouse pointing in
graphical user interfaces very difficult for some people. This article explores
goal crossing as an alternative strategy for more accessible target
acquisition. In goal crossing, targets are boundaries that are simply crossed
by the mouse cursor. Thus, goal crossing avoids the two aforementioned
problems. To date, however, researchers have not examined the feasibility of
goal crossing for people with motor difficulties. We therefore present a study
comparing area pointing and goal crossing. Our performance results indicate
that although Fitts' throughput for able-bodied users is higher for area
pointing than for goal crossing (4.72 vs. 3.61 bits/s), the opposite is true
for users with motor impairments (2.34 vs. 2.88 bits/s). However, error rates
are higher for goal crossing than for area pointing under a strict definition
of crossing errors (6.23% vs. 1.94%). We also present path analyses and an
examination of submovement velocity, acceleration, and jerk (the change in
acceleration over time). These results show marked differences between crossing
and pointing and almost categorically favor crossing. An important finding is
that crossing reduces jerk for both participant groups, indicating more fluid,
stable motion. To help realize the potential of goal crossing for computer
access, we offer design concepts for crossing widgets that address the
occlusion problem, which occurs when one crossing goal obscures another in
persistent mouse-cursor interfaces. This work provides the motivation and
initial steps for further exploration of goal crossing on the desktop, and may
help researchers and designers to radically reshape user interfaces to provide
accessible goal crossing, thereby lowering barriers to access. Keywords: Fitts' law, Steering law, Target acquisition, area pointing, goal crossing,
motor impairments, mouse pointing, movement microstructure, path analysis,
submovements, throughput | |||
| The Field Evaluation of a Mobile Digital Image Communication Application Designed for People with Aphasia | | BIBAK | Full-Text | 5 | |
| Meghan Allen; Joanna McGrenere; Barbara Purves | |||
| PhotoTalk is an application for a mobile device that allows people with
aphasia to capture and manage digital photographs to support face-to-face
communication. Unlike any other augmentative and alternative communication
device for people with aphasia, PhotoTalk focuses solely on image capture and
organization and is designed to be used independently. Our project used a
streamlined process with three phases: (1) a rapid participatory design and
development phase with two speech-language pathologists acting as
representative users, (2) an informal usability study with five aphasic
participants, which caught usability problems and provided preliminary feedback
on the usefulness of PhotoTalk, and (3) a one-month field evaluation with two
aphasic participants followed by a one-month secondary field evaluation with
one aphasic participant, which showed that they all used it regularly and
relatively independently, although not always for its intended communicative
purpose. Our field evaluations demonstrated PhotoTalk's promise in terms of its
usability and usefulness in everyday communication. Keywords: AAC devices, aphasia, cognitive disability, evaluation, field study, mobile
technology, participatory design | |||
| Sibylle, An Assistive Communication System Adapting to the Context and Its User | | BIBAK | Full-Text | 6 | |
| Tonio Wandmacher; Jean-Yves Antoine; Franck Poirier; Jean-Paul Départe | |||
| In this article, we describe the latest version of Sibylle, an AAC system
that permits persons who have severe physical disabilities to enter text with
any computer application, as well as to compose messages to be read out through
speech synthesis. The system consists of a virtual keyboard comprising a set of
keypads that allow for the entering of characters or full words by a
single-switch selection process. It also includes a sophisticated word
prediction component which dynamically calculates the most appropriate words
for a given context. This component is auto-adaptive, that is, it learns with
every text the user enters. It thus adapts its predictions to the user's
language and the current topic of communication as well. So far, the system
works for French, German and English. Earlier versions of Sibylle have been
used since 2001 in a rehabilitation center (Kerpape, France). Keywords: Augmentative and alternative communication, keystroke saving rate, latent
semantic analysis, user adaptation, virtual keyboard, word prediction | |||
| Computers and People with Disabilities | | BIBAK | Full-Text | 7 | |
| Ephraim P. Glinert; Bryant W. York | |||
| Editors' comments: “Computers and People with Disabilities” is a
reprint of an article originally published in Communications of the ACM in
1992. In this article, Glinert and York issued a “call-to-arms” for
research and development on technologies for people with disabilities.
Specifically, they highlighted that human-computer interfaces at the time
generally failed to take into account the needs of disabled users. Their
challenge was to change computing culture to address this need. Their article
remains timely today in its consideration of government, industry, and private
foundations working with researchers to achieve accessible technology. With the
recent launch of Transactions on Accessible Computing, this seems an
appropriate time to consider progress in the field since, as well as current
research trends.
The reprinting of this article is followed by four commentaries by leaders in accessibility research. Each was cited in the 1992 article and each now gives their view on how the field has progressed since that time. In their commentaries, some themes emerge and new technologies are discussed. In short, their commentaries point to both a great deal of progress and a lack of progress. All four of the commentators note areas where computing continues to present barriers rather than assist users with disabilities. Alistair Edwards sets the stage with a look back at interfaces and input technologies popular in 1992, with attention paid to access problems related to graphical user interfaces (GUIs) that have consumed much research energy since 1992. Alan Newell highlights disability concerns that were not given large research consideration in 1992, but which have now become significant due, in large part, to changes in global demographics. Specifically, he brings visibility to research on older adults and cognitively disabled users. A number of advances in technology and methodology since 1992 are discussed by the commentators. The ubiquity of computing and its critical adoption in the world today are highlighted. The commentators reflect, for example, on technologies produced by research for disabled users that have now impacted mainstream offerings on standards for accessibility that have emerged worldwide and their impact and on assistive technologies that have been developed. Critically, the proliferation of the World Wide Web was not foreseen in 1992 and its use by people with disabilities is discussed. Gregg Vanderheiden considers the opportunity afforded by the Web to provide widespread availability of accessible software. Glinert and York discussed the need for design for disability. While research relevant to users with disabilities is gaining momentum, the commentators indicate that users with disabilities still struggle with much of today's IT. The commentators note current trends toward designs that take into account disabled users. Notably, Richard Ladner ends his commentary by mentioning the issue of empowerment. Users with disabilities have moved beyond simply needing the protections of regulation that were emerging in 1992, to being active participants in designing solutions to allow full participation in the current social, political, and economic environments. Together, these articles provide a great deal of food for thought on technology advances and new considerations of accessible technology. Has the change in computing culture envisioned by Glinert and York taken hold? Vicki L. Hanson and Andrew Sears Co-Editors in Chief Keywords: Accessibility, HCI, Web, inclusive design, interfaces, ubiquitous computing,
universal access | |||
| Keeping Up with Technology: Commentary on "Computers and People with Disabilities" | | BIBAK | Full-Text | 8 | |
| Alistair D. N. Edwards | |||
| This is a personal response to rereading the Glinert and York [1992] article
“Computers and People with Disabilities.” Comparing the world of
assistive technology as it was in 1992 and as it now appears is instructive in
terms of the things which have changed -- and those which have not. The
technology has certainly developed. This applies both to the mainstream and to
the assistive technology which aims to make the mainstream accessible. So, in
1992, the GUI was a threat to visually impaired computer users; now there are
powerful screen readers available. Yet what does not appear to have changed
much is the fact that assistive technologies continue to lag behind the
mainstream, constantly having to “catch up.” Also, while there has
been some increase in awareness of the need for accessibility, there is still
scope for that awareness to be translated into action. Keywords: Interfaces | |||
| Accessible Computing -- Past Trends and Future Suggestions: Commentary on "Computers and People with Disabilities" | | BIBAK | Full-Text | 9 | |
| Alan F. Newell | |||
| This article gives a personal perspective on Glinert and York's 1992 paper,
focusing on whether and how the situation has changed over the past 15 years,
and makes recommendations for the future of the field of accessible computing
with a particular focus on the needs of older people and people with cognitive
dysfunction. Keywords: Assistive technology, cognitive dysfunction, inclusive design, older and
disabled people, theater in design | |||
| Ubiquitous Accessibility, Common Technology Core, and Micro-Assistive Technology: Commentary on "Computers and People with Disabilities" | | BIBAK | Full-Text | 10 | |
| Gregg C. Vanderheiden | |||
| Much has changed since 1992 when the original CACM article by Ephraim
Glinert and Bryant York was published. In the early 1990's, accessibility was
mostly an add-on, with only Apple computers having built-in access. Computers
were playing an increasingly important role in education and employment, but
had not yet completely integrated themselves into all aspects of life as
completely as they have today. The World Wide Web as we know it had not yet
been born. Today there are accessibility features built directly into every
major operating system, and one OS even includes a built-in screen reader.
Assistive technologies are more numerous and capable. And awareness of the
importance of access is much higher. However, some things have not changed.
Assistive technologies lag behind mainstream technologies in both compatibility
and functionality. Effective assistive technologies are often beyond the
financial reach of those who need them. Effective assistive technologies are
not available in many countries and many languages, even though technology is
reaching into education, employment, and daily living of more countries and
more people in each country every year. In moving forward we need to build on
what we have achieved and explore new concepts, such as a common technical
core, ubiquitous accessibility, micro assistive technology, and free public
accessibility. Cooperative and collaborative approaches also need to be
explored if we are to have any hope of catching up and keeping up with the
ever-accelerating mainstream information and communication technologies. Keywords: Interfaces, micro-AT, ubiquitous accessibility | |||
| Access and Empowerment: Commentary on "Computers and People with Disabilities" | | BIBAK | Full-Text | 11 | |
| Richard E. Ladner | |||
| A number of positive changes have taken place since Glinert and York's 1992
call-to-arms. Progress reviewed in this article includes evolving
considerations of universal design in the marketplace, ubiquitous computing
with accessibility features, increasing computing research and conference
venues that address needs of users with disabilities, and attention to the
importance of user empowerment in development. Keywords: Universal design, Web, ubiquitous computing, user-centered design | |||
| Multimodal Trajectory Playback for Teaching Shape Information and Trajectories to Visually Impaired Computer Users | | BIBAK | Full-Text | 12 | |
| Andrew Crossan; Stephen Brewster | |||
| There are difficulties in presenting nontextual or dynamic information to
blind or visually impaired users through computers. This article examines the
potential of haptic and auditory trajectory playback as a method of teaching
shapes and gestures to visually impaired people. Two studies are described
which test the success of teaching simple shapes. The first study examines
haptic trajectory playback alone, played through a force-feedback device, and
compares performance of visually impaired users with sighted users. It
demonstrates that the task is significantly harder for visually impaired users.
The second study builds on these results, combining force-feedback with audio
to teach visually impaired users to recreate shapes. The results suggest that
users performed significantly better when presented with multimodal haptic and
audio playback of the shape, rather than haptic only. Finally, an initial test
of these ideas in an application context is described, with sighted
participants describing drawings to visually impaired participants through
touch and sound. This study demonstrates in what situations trajectory playback
can prove a useful role in a collaborative setting. Keywords: Accessibility, evaluation, multimodal, trajectory playback | |||
| Introduction to the Special Issue on AAC | | BIBAK | Full-Text | 13 | |
| Kathleen F. McCoy; Annalu Waller | |||
| This article presents an introduction to the special issue on Augmentative
and Alternative Communication (AAC). Keywords: Alternative and augmentative communication, human-computer interaction | |||
| Conception and Experimentation of a Communication Device with Adaptive Scanning | | BIBAK | Full-Text | 14 | |
| Souhir Ghedira; Pierre Pino; Guy Bourhis | |||
| For some people with motor disabilities and speech disorders, the only way
to communicate and to have some control over their environment is through the
use of a controlled scanning system operated by a single switch. The main
problem with these systems is that the communication process tends to be
exceedingly slow, since the system must scan through the available choices one
at a time until the desired message is reached. One way of raising the speed of
message selection is to optimize the elementary scanning delay in real time so
that it allows the user to make selections as quickly as possible without
making too many errors. With this objective in mind, this article presents a
method for optimizing the scanning delay, which is based on an analysis of the
data recorded in “log files” while applying the EDiTH system
[Digital Teleaction Environment for People with Disabilities]. This analysis
makes it possible to develop a human-machine interaction model specific to the
study, and then to establish an adaptive algorithm for the calculation of the
scanning delay. The results obtained with imposed scenarios and then in
ecological situations provides a confirmation that our algorithms are effective
in dynamically adapting a scan speed. The main advantage offered by the
procedure proposed is that it works on timing information alone and thus does
not require any knowledge of the scanning device itself. This allows it to work
with any scanning device. Keywords: Alternative communication, Model Human Processor, adaptative scanning rate,
modeling, scanning system | |||
| The Effect of Voice Output on AAC-Supported Conversations of Persons with Alzheimer's Disease | | BIBAK | Full-Text | 15 | |
| Melanie Fried-Oken; Charity Rowland; Glory Baker; Mayling Dixon; Carolyn Mills; Darlene Schultz; Barry Oken | |||
| The purpose of this study was to determine whether the presence or absence
of digitized 1-2-word voice output on a direct selection, customized
Augmentative and Alternative Communication (AAC) device would affect the
impoverished conversations of persons with dementia. Thirty adults with
moderate Alzheimer’s disease participated in two personally relevant
conversations with an AAC device. For twelve of the participants the AAC device
included voice output. The AAC device was the FlexiboardTM containing
sixteen messages needed to discuss a favorite autobiographical topic chosen by
the participant and his/her family caregivers. Ten-minute conversations were
videotaped in participants’ residences and analyzed for four
conversational measures related to the participants’ communicative
behavior. Results show that AAC devices with digitized voice output depress
conversational performance and distract participants with moderate
Alzheimer’s disease as compared to similar devices without voice output.
There were significantly more 1-word utterances and fewer total utterances when
AAC devices included voice output, and the rate of topic
elaborations/initiations was significantly lower when voice output was present.
Discussion about the novelty of voice output for this population of elders and
the need to train elders to use this technology is provided. Keywords: Alzheimer’s disease, Augmentative and Alternative Communication (AAC),
Dementia, digitized speech synthesis, language | |||
| Evaluating the STANDUP Pun Generating Software with Children with Cerebral Palsy | | BIBAK | Full-Text | 16 | |
| Annalu Waller; Rolf Black; David A. O'Mara; Helen Pain; Graeme Ritchie; Ruli Manurung | |||
| The interactive STANDUP software was developed to provide children who use
augmentative and alternative communication (AAC) with a “language
playground.” The software provides appropriate functionality for users
with physical, speech, and language impairments to generate and tell novel
punning riddles at different levels of complexity. STANDUP was evaluated with
nine children with cerebral palsy during an eight-week study. Results show that
the participants were able to generate and tell novel jokes with minimal or no
support. The use of STANDUP impacted favorably on general AAC use. The study
results also suggested that STANDUP could potentially have a positive effect on
social and pragmatic skills. Further research to investigate the impact of
STANDUP on communication skills is proposed. Suggestions for future software
development include providing users with opportunities to complete jokes and to
integrate online dictionaries when new vocabulary is encountered. Keywords: Alternative and augmentative communication, computational humor, speech
generation devices | |||
| User Interaction with Word Prediction: The Effects of Prediction Quality | | BIBAK | Full-Text | 17 | |
| Keith Trnka; John McCaw; Debra Yarrington; Kathleen F. McCoy; Christopher Pennington | |||
| Word prediction systems can reduce the number of keystrokes required to form
a message in a letter-based AAC system. It has been questioned, however,
whether such savings translate into an enhanced communication rate due to the
additional overhead (e.g., shifting of focus and repeated scanning of a
prediction list) required in using such a system. Our hypothesis is that word
prediction has high potential for enhancing AAC communication rate, but the
amount is dependent in a complex way on the accuracy of the predictions. Due to
significant user interface variations in AAC systems and the potential bias of
prior word prediction experience on existing devices, this hypothesis is
difficult to verify. We present a study of two different word prediction
methods compared against letter-by-letter entry at simulated AAC communication
rates. We find that word prediction systems can in fact speed communication
rate (an advanced system gave a 58.6% improvement), and that a more accurate
word prediction system can raise the communication rate higher than is
explained by the additional accuracy of the system alone due to better
utilization (93.6% utilization for advanced versus 78.2% for basic). Keywords: Word prediction, communication rate, user study | |||