Geoff Loftus: On
the benefits of bogus data
Abstract
The responses in a psychological
experiment traditionally come from living subjects drawn from whatever population
is under investigation. Another potential source of responses is a computer
program designed to mimic the subjects' responses. While one would not generally
want to use these computer-generated or "bogus" responses as the ultimate basis
for making conclusions about psychological processes, they are nevertheless
useful in three respects. The first is methodological: One can test out almost
all aspects of the planned experiment (e.g., computer programs that run the
experiment and analyze the data from it) without the expense, time, and hassle
of using actual subjects. The second is statistical: One can simulate various
kinds of randomization and counterbalancing and observe the consequences for
the orderliness of the data. The third is theoretical: To generate bogus data,
one is forced to generate a theory of how the responses are produced and how
they are affected by the various experimental manipulations. The process of
so doing is often accompanied by remarkable insights into the nature of possible
theories of the processes under investigation, along with immediate feedback
about detailed predictions of such theories.