Two studies investigated how planning affects intention-behavior consistenc
y. In Study 1 an experimental group and control group which each consisted
of 14 undergraduates were requested in computerized interviews to indicate
which activities they intended to perform on the following day. Subjects in
the experimental group were also requested in a second phase of the interv
iews to specify when and where they intended to perform the activities. The
results showed that activities for which time and place had been specified
were more likely to be performed. In Study 2 another 75 undergraduates vol
unteered to participate in an experiment in which they were requested to pe
rform an activity (reporting mood effects of reading a prose excerpt) by th
emselves on one of three following days. One group of subjects only agreed
to perform the activity, another group agreed to perform the activity as we
ll as indicated when and where they would do it, and a third group in addit
ion to this indicated which other activities they would perform on the same
day. In support of the hypothesis that planning an activity increases the
likelihood that it will be performed, the results showed that subjects who
indicated other activities more frequently performed the target activity. M
ore efficient time management resulting from planning may account for the f
indings, although further research is needed to show this conclusively.