New study could impact Web design, other industries

New
study could impact Web design, other industries
…………………………………………………………………

BY B.J. ALMOND
Rice News Staff

A model of human
thinking and performance that has been studied by a Rice
psychologist can predict how well people locate and select
various options on a computer screen. The model has implications
for designing air-traffic-control monitors, in-car navigation
systems, Web pages and other computer displays in ways that
people can process information more efficiently.

“Our theory
and model allow scientists to make predictions about human
performance on tasks that involve computer displays,”
said Michael Byrne, assistant professor of psychology at
Rice. “We can tell, for example, where to position
information on a computer screen so that the user is more
likely to see it quickly.”

Byrne conducted
the research at Carnegie Mellon University before joining
the faculty at Rice, where he analyzed the results that
are published in the July issue of the International Journal
of Human Computer Studies.

“Understanding
the interaction of a user with a designed device like a
computer requires a clear understanding of three components,”
Byrne said. “The user’s cognitive, perceptual
and motor capabilities, the task and the device used to
accomplish the task can impact the result.”

Byrne showed
each of the 11 participants in his study more than 100 questions
that involved identifying a particular number or letter
in lists of random numbers and letters on a computer screen.
He timed how long it took the participants to spot the selected
symbols. A camera mounted on a headband worn by the participants
tracked their eye movements.

Using a theory
of cognition known as ACT-R/PM and an eye-tracking model,
Byrne predicted how long it would take the participants
to click on the targeted items. He also predicted the other
items they would look at en route to the targeted items,
based on the characters or numbers they were likely to fixate
on and the order in which they were likely to read information
on the display.

Byrne found
that his predictions averaged within 15 percent of participants’
actual response times — “close enough to be useful
to designers,” he said.

Engineers who
design air-traffic-control monitors, for example, could
use the theory and model to position critical information
on a screen where the user is most likely to see it first.

“Keeping
up with the volume of information on a computer display
is often a problem,” Byrne said. “A designer can
optimize the rate at which people can process information
on the screen by using the theory and model we studied.
A strategic placement of menu items can make it possible
for people to read the most important information fast enough
to keep up with their work so they don’t end up in
a situation where they’re likely to make errors.”

Byrne’s
research was supported by the National Science Foundation,
the Office of Naval Research, the National Institute of
Mental Health and NASA.