Page 172 - [Uma_Sekaran]_Research_methods_for_business__a_sk(BookZZ.org)

156 EXPERIMENTAL DESIGNS

the morale of employees. She set up three experimental groups and one control group
for the purpose and assigned members to each of the groups randomly. The three
experimental groups were headed by an autocratic leader, a democratic leader, and a
laissez-faire leader, respectively.
The members in the three experimental groups were administered a pretest. Since
the control group was not exposed to any treatment, they were not given a pretest.
As the experiment progressed, two members in the democratic treatment group got
quite excited and started moving around to the other members saying that the par-
ticipative atmosphere was “great” and “performance was bound to be high in this
group.” Two members from each of the autocratic and laissez-faire groups left after
the first hour saying they had to go and could no longer participate in the experi-
ment. After 2 hours of activities, a posttest was administered to all the participants,
including the control group members, on the same lines as the pretest.

History Effects. The action of the two members in the participative group by
way of unexpectedly moving around in an excited manner and remarking that
participative leadership is “great” and the “performance is bound to be high in
this group” might have boosted the morale of all the members in the group. It
would be difficult to separate out how much of the increase in morale was due
to the participative condition alone and how much to the sudden enthusiasm dis-
played by the two members.

Maturation. It is doubtful that maturation will have any effects on morale in
this situation, since the passage of time, in itself, may not have anything much
to do with increase or decrease in morale.

Testing. The pretests are likely to have sensitized the respondents to the
posttest. Thus, testing effects would exist. However, if all the groups had been
given both the pre- and the posttests, the testing effects across all groups would
have been taken care of (i.e., nullified) and the posttests of each of the experi-
mental groups could have been compared with that of the control group to
detect the effects of the treatment. Unfortunately, the control group was not
given the pretest, and thus, this group’s posttest scores were not biased by the
pretest—a phenomenon that could have occurred in the experimental groups.
Hence, it is incorrect, on the face of it, to compare the experimental groups’
scores with those of the control group.

Instrumentation. Since the same questionnaire has measured morale both
before and after the treatment for all members, we do not expect instrumenta-
tion bias.

Selection Bias. Since members have been randomly assigned to all groups, we
do not expect selection bias to exist.

Statistical Regression. Though not specifically stated, we can assume that all
the members participating in the experiment were selected randomly from a