Characteristics and step of Experimental Research.

In the conduct of an experiment, there are three major ingredients. These are Control,Manipulation and Observation 

Control:

This is very important in experimental studies because without it, it is impossible to evaluate
unambiguously the effect of an independent variable. The major purpose of control is to arrange a situation I which the effects of variables only can be measured. We can simply say that control is the term used to indicate your procedures or methods fro eliminating the differential effects of all variables extraneous to the purpose of the study. Note that an extraneous variable is one which is not related to the purpose of the study but which may affect or have influence on the dependent variable.

 Manipulation

This refers to a deliberate operation performed by the researcher. In the behavioural sciences and
education, the manipulation of a variable takes a characteristic form in which the experimenter imposes a predetermined set of varied conditions on the subjects. This set of varied conditions is referred to as the independent variable, the experimental variable or the treatment variable.

Observation:

In an experimental study, we are interested to know the effect of the manipulation of the independent variable on a dependent variable. Therefore you make observations with respect to some characteristics of the behaviour of the subjects used in the research. These observations, which are most of the times quantitative in nature, may constitute the dependent variable. For instance in an educational situation, we are interested to know the performance of students after going through some learning.


These performances can only be estimated through measures like scores in a test. If we want to explain or predict students performance we use their test scores. It means that these test scores are the dependent variables or observations rather than performance.

Steps in Experimental Research

There are number of steps involved in experimental studies. The steps that will lead you to the
actual experiment are:


i. Making a survey of the literature related to the problem.

ii. Identification and definition of the problem.

iii. Formulating the hypotheses and defining basic terms and variables. 

Hypotheses must be formulated in an experimental research. This is because they suggest how an antecedent condition or phenomenon or the independent variable is related to the occurrence of another condition, phenomenon, event or effect otherwise called the dependent variable.

For you to test the hypothesis, you have to attempt to control all the conditions except the
independent variable which you manipulate. 

 You now observe if the effect on the dependent variable is as a result of the exposure to the independent variable.


iv. Construction of the experimental plan. This refers to the conceptual frame work in which the experiment is conducted. The plan involves:

a. Identification of all the non-experimental variables that might contaminate the experiment and determine how to control them.
b. Selection of a research design
c. Selection of the sample of subjects to represent a given population and the assignment of
d. the subjects to groups and experimental treatments to the groups. Construction or selection and validation of the instruments for measuring the outcomes of 

the experiment.
e. Outlining the procedures for collecting the data and possibly conducting a plot or trial test to perfect the instrument or design.
f. State the statistical or null hypothesis.

These steps above will bring you the actual experiment. After the experiment, you apply statistical measures to the data obtained and then test the significance of the results.

SELF ASSESSMENT EXERCISE 1

i. What is experimental research?
ii. What are the characteristics of experimental research?

 EXPERIMENTAL DESIGN

You have to note that a well developed design will provide the structure and strategy for you to
control the investigation and get dependable answers to the questions raised in the problem or hypothesis. Again you have to note also that the nature of the problem determines the appropriateness of the design. Let us look at the various types of designs.