A. Meaning of Experimental Research:

The experimental method in educational research is the
application and adaptation of the classical method of experimentation. It is a scientifically sophisticated method. It provides a method of investigation to derive basic relationships among phenomena under controlled condition or, more simply, to identify the conditions underlying the occurrence of a given
phenomenon. Experimental research is the description and analysis of what will be, or what will occur, under carefully controlled conditions.

Experimenters manipulate certain stimuli, treatments or environmental conditions and observe how the condition or behaviour of the subject is affected or changed. Such manipulations are deliberate and systematic. The researchers must be aware of other factors that could influence the outcome and remove or
control them in such a way that it will establish a logical association
between manipulated factors and observed factors.

Experimental research provides a method of hypothesis testing. Hypothesis is the heart of experimental research. After the
experimenter defines a problem he has to propose a tentative
answer to the problem or hypothesis. Further, he has to test the hypothesis and confirm or disconfirm it.

Although, the experimental method has greatest utility in the laboratory, it has been effectively applied non-laboratory settings such as the classroom. The immediate purpose of
experimentation is to predict events in the experimental setting. The ultimate purpose is to generalize the variable relationships so that they may be applied outside the laboratory to a wider population of interest.

B. Characteristics of Experimental Method:

There are four essential characteristics of experimental
research: (i) Cool, (ii) Manipulation (iii) Observation and (iv)
Replication.

Control : Variables that are not of direct interest to the researcher,
called extraneous variables, need to be controlled. Control refers to
removing or minimising the influence of such variables by several
methods such as: randomisation or random assignment of subjects
to groups; matching subjects on extraneous variable(s) and then
assigning subjects randomly to groups; making groups that are as
homogenous as possible on extraneous variable(s); application of
statistical technique of analysis of covariance (ANCOVA); balancing
means and standard deviations of the groups.

Manipulation : Manipulation refers to a deliberate operation of the conditions by the researcher. In this process, a pre-determined set
of conditions, called independent variable or experimental variable.
It is also called treatment variable. Such variables are imposed on
the subjects of experiment. In specific terms manipulation refers to
deliberate operation of independent variable on the subjects of
experimental group by the researcher to observe its effect. Sex,
socio-economic status, intelligence, method of teaching, training or
qualification of teacher, and classroom environment are the major
independent variables in educational research. If the researcher, for
example, wants to study the effect of ‘X’ method of teaching on the
achievement of students in mathematics, the independent variable here is the method of teaching. The researcher in this experiment needs to manipulate ‘X’ i.e. the method of teaching. In other words, the researcher has to teach the experimental groups using ‘X’
method and see its effect on achievement.

Observation : In experimental research, the experimenter
observes the effect of the manipulation of the independent variable on dependent variable. The dependent variable, for example, may
be performance or achievement in a task.

Replication : Replication is a matter of conducting a number of sub-experiments, instead of one experiment only, within the
framework of the same experimental design. The researcher may
make a multiple comparison of a number of cases of the control
group and a number of cases of the experimental group. In some
experimental situations, a number of control and experimental groups, each consisting of equivalent subjects, are combined within a single experiment.