Applications 3111324(a)(b)Figure 11.6 Illustration of various display-control mapping configurations
for (a) stove tops (with specific burner-control pairings indicated by letters)
and (b) Duncan’s (1977) four-choice tasks (with specific S-R pairings indi-
cated by arrows).
selection has been basic in nature, the results obtained from
this research are of considerable relevance to applications in-
volving interface design. It is widely accepted that a user-
friendly design must adhere to principles of action selection in
general and SRC in particular (see Andre & Wickens, 1990).
In a classic study of stove configurations, Chapanis and
Lindenbaum (1959) evaluated four control-burner arrange-
ments (see Figure 11.6a). The experimenter demonstrated the
individual pairings of burners to controls for one of the four
stoves, and then instructed subjects to push the assigned con-
trol to the burner that was lit. Subjects showed shorter RT for
Design 1 than Designs 2–4, for which RT did not differ ini-
tially. Furthermore, no errors were made for the mappings of
Design 1, whereas the overall error rate was 6%, 10%, and
11% for Designs 2–4, respectively. Practice significantly re-
duced RT and errors for Design 2 compared to Designs 3 and
4, but performance was still worse than with Design 1. When
naive subjects were asked which control-burner configura-
tion was the best, most selected Design 1. However, they
were equally divided about whether Design 2, 3, or 4 was
second best. Thus, although after practice performance was
better with Design 2 than Designs 3 and 4, naive subjects did
not anticipate this difference.
In a more recent study, Payne (1995) asked naive subjects
to rank from easiest to hardest the four mappings of a four-
choice SRC task in which the inner or outer pairs are mapped
compatibly or incompatibly (Duncan, 1977; see Figure 11.6b).
He compared the subjective rankings to RT measures obtained
by Duncan. Similar to the results of the stove study, subjects
had little difficulty identifying Design 4 as the easiest mapping
because it was a direct mapping. However, more subjects
rated Design 1 (in which both inner and outer pairs were
mapped incompatibly) as being harder than Designs 2 and 3
(in which only one pair was mapped compatibly and the other
incompatibly), even though actual performance was second
best on Design 1.
The deleterious effect of mixed mappings illustrated in
Duncan’s (1977) study, as well as in that of Shaffer (1965),
discussed in the “Task Switching” section, indicates that the
context in which the display-control configuration is placed
affects performance. Most compatibility studies evaluate per-
formance of specific S-R mappings in isolation. However,
when more than one S-R mapping is used, the benefit that one
might expect from a compatible mapping is not always evi-
dent. Moreover, if two tasks must be performed simultane-
ously, it may be easier to perform them together when they
have the same incompatible mapping than when one has a
compatible mapping and the other does not (Duncan, 1979).
Andre and Wickens (1990) refer to this benefit as one of
global consistency and note that it may sometimes be more
important than local compatibility.
Because the amount of experience with specific S-R map-
pings is a major factor in efficiency of action selection, de-
signers must take into account the stereotypic behavior of the
specific population for whom a product or system is being
designed. For example, from years of experience, Americans
are more likely to flick a light switch down when they intend
to turn a light off, whereas Englishmen are more likely to