1. Research project.
Background
My research was oriented towards to study adaptive interfaces and build a
Biologically Inspired Adaptive Interface, which will function as the immune system
in human body. An adaptive user interface is a software artifact that improves its
ability to interact with a user by constructing a user model based on partial experience
with that user. (Pat Langley, 1999)
We had a team of three graduate students. My primary responsibility was to
design the software based upon the original software. The original software was
designed in Quick Basic by NASA people in 1980. Once we had the working
software, our team made changes accordingly, did usability testing and the pilot
studies. Every week we used to have a group meeting and presentation on the work
done / to be done.
We developed an interface, which was designed in Visual Basic 6.0 and is one
of the tasks of NASA’s Multi Attribute Task Battery (MATB). The resource
management task, a version of the MATB system (Comstock et al., 1992) was
modified and isolated from the other three tasks. Following are the snapshots of the
original and the developed interface.
Fig1: NASA’s MATB
Fig 2: Resource Management System
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The goal of the operator was to keep the fuel level of the two main tanks at the
desired levels. The operator must monitor all tank leaks, pump malfunctions and
failures, changing fuel level goal levels, and the repairperson on duty in order to
achieve optimal performance.
1.1. What is it we wanted to learn?
The simulation was designed like a game where users were supposed to
perform the task using the interface. The main concern was to make the task
difficult enough to notice a drop-off in performance of the operator. We tested the
interface using three pilot studies and finally an interface was designed which was
difficult enough.
1.2. Why did we want to address the problem?
The goal of the research was to develop a biologically inspired adaptive
interface. To achieve this goal it was necessary to have an interface that is difficult
enough to operate and which then could be made adaptive in order to improve the
performance of the operator.
1.3. Who was the user or population of interest?
The project was at initial stage where we did only pilot studies. As it was an
academic research project the user population was students from Wright State
University, Dayton, OHIO. These subjects were either grad or undergrad students
who had basic knowledge of computer.
1.4.
The research method we used.
The experimental design chosen was Within Subjects and the order of
trials was counterbalanced. Performance in this case was dependent on the amount
of time (dependent variable) that the subjects were able to keep the fuel levels of the
two main tanks within the acceptable ranges. The independent variables were tank
leaks, pump malfunctions and failures, changing fuel level goal levels, and the
repairperson on duty.
A point system was developed to track subject performance. Subjects
began the experiment with zero points and with the fuel level in both of the main
tanks within range. Updated every second, whenever the fuel level in one of the
tanks fell out of the acceptable range, the subject received a score of –1. Whenever
the fuel level in one of the tanks came back within range, the subject received a
score of +1. Using this system, the subject could have a score somewhere between
–2 and 0 at any point in time. A –2 indicated that the fuel level in both tanks was
out of range, a –1 indicated that the fuel level in only one tank was out of range, and
a 0 indicated that the subject was performing optimally with both main tanks within
range.
Output from the task is collected and saved to output files for each trial.
The file was updated automatically every second, and with the occurrence of a userinitiated events that occur between these automatic updates with an accuracy of
1/100th of a second. Data that were collected include:
 Pump status (On/Off/Malfunctioning/Failed-Fixed)
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 Pump flow rate (High/Normal)
 Tank fuel levels (Actual fuel level)
 Optimal fuel level range for tanks (Optimal Lower and Upper fuel level
for both tanks)
 Tanks in or out of optimal range
 Repair person on duty
 Tank leakages and fixes
Subjects were given pre and post questionnaires through which we
collected information regarding computer and computer games background of the
subjects and feedback about the interface.
1.5. How did we analyze our data?
Graphs were created for each of the subjects to try to determine if the task
was difficult enough to notice a drop-off in performance.
Fig 3: Sample graph
1.6. What did we learn?
As mentioned above we did three pilot studies and made the changes
accordingly.
Pilot study 1
Subjects ran three different trials for varying lengths of time: 5, 10, and
15-minute sessions were used, each equally divided into three time periods for an
easy, medium, and hard scenario.
The graphs did not show any instances where performance dropped off.
The task was changed for the second pilot study to make it more difficult. It was
decided that the 15-minute trial time should be used in case we decided to include
measurement of physiological data in the study. A task time of five or ten
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minutes would not have been long enough to collect meaningful physiological
data.
Pilot study 2
The auditory repairperson task was introduced in the second pilot study.
Subjects were now not only responsible for keeping the fuel levels in the
acceptable ranges while monitoring for the other task occurrences, but they had
the added responsibility of choosing the correct repairperson to fix a
malfunctioning pump. Fixing a malfunctioning pump has obvious advantages
over letting it fail completely, so we could assume that the subject is interested in
paying attention to these auditory cues.
The graphs still did not show any point where performance dropped off
completely. A third pilot study was prepared in which subjects would be trained
for a longer amount of time on the task.
Pilot study 3
The task presented in the third pilot study was the same as in the second.
Subjects were required to participate in two days of testing so that a more
extensive training session could be presented to them.
The results of this study gave a clear idea that the task is too difficult with
only 5 seconds between repair people. The fourth pilot study was planned with
more number of subjects to ensure the results from the third pilot study. But the
project was terminated as our advisor left the university.
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