2001 Conference Proceedings
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THE AUDIO-ACCESSIBLE GRAPHING CALCULATOR
John A. Gardner
Science Access Project Oregon State University Department of
Physics Corvallis, OR 97331-6507 http://dots.physics.orst.edu/
Steven Sahyun E-mail: firstname.lastname@example.org
Department of Physics
Lewis and Clark College
The Audio-Accessible Graphing Calculator is a self-voicing
Windows application that has been under development and testing
for some time by the Science Access Project. It includes the
Beta testing was conducted in 2000, and in this paper we give an
overview of the results of that beta test. In the presentation we
will demonstrate how to use the calculator.
- compute and display visually either of two functions, their
sum, or their difference,
- display the above as an audio tone plot,
- permit piece-by-piece audio browsing
- print the above to any Windows printer including the Tiger
tactile graphics embosser,
- be used as a universally usable on-screen scientific
- be used as a powerful expression evaluator
- input tabulated data for display,
- compute statistical functions for tabulated data
Summary of Beta Test Results
The Accessible Graphing Calculator (AGC) beta-test was run from
May until mid-July, 2000. To qualify as a beta-tester, volunteers
filled out a demographic survey form. Upon acceptance, volunteers
then downloaded the AGC program from a Web site, or were sent
copies of the program on CDROM.
There were 33 people who downloaded the AGC during the beta-test
period. Some of the people who downloaded the program were
individual testers, although there were several people
responsible for installation and testing on many computers. Six
people (some of whom downloaded the program) were sent CDROMs.
From data collected in the initial survey form, beta-testers
ranged in experience from novice users to experienced
programmers. Education ranged from high school students to Ph.Ds.
Occupations generally fell into three categories: Adaptive
Technology Specialists, students, and educators.
The locations of beta testers ranged world-wide with most
residing in the US or Canada. Other countries that had testers
were Germany, Egypt, Australia, and Palestine.
Testers heard about the beta test from demonstrations of the AGC
at CSUN and other conferences (ICCHP), personal contacts, word of
mouth (from special education teachers' ListServes and the
Blind-Tech ListServ), and from the Science Access Project or
National Science Foundation Web sites. Many (28) of the
beta-testers were familiar with screen reading programs (such as
Jaws, Window-Eyes, and Outspoken) although they did not
necessarily use them. Only 8 were not familiar with screen
Eight people reported that the program crashed during
installation. It is well-known that many older commercial speech
engines have fatal conflicts with the MS SAPI (speech engine)
used by the AGC. When these old speech engines were uninstalled,
the AGC program usually installed. No conflicts were found with
the popular Eloquent speech engine used with many screen readers.
We are aware of only one beta tester who removed the conflicting
speech engines but was still unable to load the AGC program, and
we have thus far been unable to find the reason for this person's
Beta test volunteers were sent an e-mail survey about their
experiences with the AGC. For testers who did not respond to the
initial survey within a specified time frame, copies of the
survey were e-mailed to them several times. The survey consisted
of 22 questions (some of which had multiple parts) regarding
their impressions about the program. There were 11 subjects who
responded to the survey.
The AGC features that testers found particularly useful were:
One feature that testers found annoying was that the help file is
a standard Microsoft application that is used in the standard
Microsoft-recommended way. This application is not self-voicing,
so a screen reader is required to read it in audio. This
annoyance was partially remedied in a later version by including
a self-voicing help file accessed from the help menu, so users
could choose their preferred format.
- the keypad scientific calculator and the expression evaluator
which allow for easy entry of scientific functions,
- the self-voicing feature which allows for easy access to all
parts of the AGC,
- the auditory graph display,
- capability to print graphs to Tiger or swell paper,
- capability of finding maximum and minimum points on a
- capability for generating data tables.
Other features that were criticized by some users were that the
text was small at times, that the on-screen calculator could not
be magnified, and that the program did not support braille
embossers. It does support standard Windows printing however so
output could be embossed with the new Tiger Tactile
Graphics Embosser or printed on swell paper from which
tactile copy can be made.
The calculator keypad was criticized by some as the buttons are
in a standard visual layout. However, in general, beta testers
found that the layout and implementation of features was
In comparison to other methods for accessing graphs, the AGC was
generally considered the best. "Where the AGC is mostly effective
is in its facility for giving the user a general sense of what
the data looks like via the audio graphing function."
Ease of entering and editing equations, navigating between the
AGC's features, and operating the data and graphing features,
were rated on average between fairly easy and very easy. Actual
However it was noted that one must read the instructions first.
One must also use the self-voicing capability for audio access.
One beta tester insisted on using a screen reader and, not
surprisingly, had a number of difficulties.
- very difficult 1,
- somewhat difficult 2,
- fairly easy 3,
- very easy 4.
On average, beta testers rated the AGC quite practical, the
number of features adequate for their needs (with the desire for
more statistical functions noted), and the general layout good.
On average, testers agreed that the benefits of using the AGC are
worth the time and effort expended in learning to use the program
and that the auditory graphs were a useful feature.
Nine of the 11 beta testers would recommend the AGC to others.
The two who did not, cited concern for the time needed to learn
and the difficulty of use with a screen reader.
Comments and Conclusions
The AGC program pleased most beta testers a great deal, although
all would be pleased if it could be made easier to learn. They
also noted several features that are unfortunate but
An on-screen keyboard cannot be magnified larger than the
screen, so if used visually by people with low vision, a screen
magnifier is required. We believe that a power user with low
vision would be best served by using the hot keys for entering
data and keep a screen magnifier on the calculator screen output.
In a future release we shall attempt to provide an alternative to
this calculator screen that can be magnified without a separate
It was also noted that the program is not really usable with a
screen reader. From the beginning, this program was intended to
be universally accessible. In order to be friendly to sighted
users one must adopt a two-dimensional screen layout for some
features, and screen reader access immediately becomes a knotty
problem. Any screen reader user who has tried to use an on-screen
keyboard program, such as the calculators bundled with Windows,
can appreciate the difficulty of using a screen reader where one
really needs an information reader. We believe that we have
solved this problem in the way it should be solved - by providing
a true audio interface. Screen readers should just be put to
sleep when focus is in the AGC program and other applications
with full audio interfaces.
Finally, several beta testers were disappointed that AGC does not
support braille embossers. Unfortunately, braille embossers do
not have the capability of accepting WYSIWYG information, so it
is not possible even in principle to emboss both the graph and
its text labels. There are applications available that can be
used to create graphs without labels to be embossed with standard
braille embossers. Many observers feel that braille embosser
resolution is just too poor for such graphs to be really useful.
Two modern technologies, the Tiger Windows Embosser and Capsule
paper, are now available that do permit fully-usable tactile
copies to be made, and these work very well with AGC.
Although there are still improvements that we intend to make in
future versions, we believe that the beta test results indicate
that we have succeeded in making a program that fills a great
need. At the time of writing this article, the AGC was not yet
commercially available, but the authors are doing their best to
introduce it commercially and hope that it is on the market by
the time of the conference.
This research was supported in part by the National Science
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