Two versions (internalized
& externalized)
of an isomorph of the “missionaries and cannibals”
problem were tested. 30 subject
solved 6 problems,
then performed a distraction task
erasing WM,
and solved 3 more problems.
Also knowledge of the
problem’s rules and states was tested.
Internalization
yielded better knowledge and reaching less dead-end
problem-states.
Time needed, steps and error-rates were
in the expected direction, but not significantly.
This
research contributes to GUI design-guidelines for
human-computer interaction of problem-solving tasks.