UNIT 6 EX-POST FACTO RESEARCH
6.1.) Forms of Research Design
On basis of the occurring events, there can be two designs or forms of research and these are P rospective research design and Retrospective research
design.
Prospective research design:
When the researcher tries to find out the future or potential results that is, the effect after treating the i ndependent variable, then the
researcher is actually trying to examine the prospective or the future results.
o For e xample, if the researcher wants to e xamine the effects of excess of smoking, then the subject may be asked to smoke under
varied conditions which may result in cancer.
Retrospective research design:
The Retrospective research design on the other hand is one in which the researcher tries to trace the history in order to find out the basic
reason behind an event. This kind of results obtained are said to be based on retrospective research design.
o For example, if the researcher wants to examine the reason behind the occurrence of cancer in a person, then they may try to trace
the possible reasons that might have led to cancer. The possibilities may be excess of smoking/ heredity/ diet habits and so on.
6.2.) Concept and Meaning of Ex-post Facto Research
The ex-post facto research is a kind of research in which the researcher predicts the possible causes behind an effect that has already
occurred.
o For example, if a child is delinquent (that is, one who indulges in criminal activities), then in order to find the basic reason behind
such delinquency, the researcher would try to find out the various events that have occurred and the many possibilities that could
have contributed to the concerned delinquent behaviour. The expected possibilities may be lack of discipline at school/ family
history/ peer effect/ neighbourhood or socialisation.
Thus, an ex-post facto research can be defined as an empirically based investigation which does not involve the researchers’ direct control
over the independent variables because they have already led to effects which can no Ex-Post Facto Research more be manipulated.
The term ex-post facto according to Landman (1988: 62) is used to refer to an experiment in which a researcher, instead of finding a
treatment, examines the effect of a naturally occurring treatment after it has occurred. In other words it is a study that attempts to discover
the pre-existing causal conditions between groups.
Characteristics of Ex-post Facto Research
Based on the concept of the ex-post factor research, it is also known as ‘causal comparative research’. Some of these characteristics are presented
below in the following paragraphs.
1) The research has a control or a comparison group
As the research is done on basis of the study of the cause which has already led to its effects, it becomes necessary for the researcher to keep a
control group, which can be used for comparison with the actual experimental group later on, in order to analyse the cause of an already
occurred event.
2) The behaviour, action, event or the treatment or the independent variable of the research cannot be manipulated or changed
As the ex-p ost research is a kind of study which tries to predict the causes on the basis of actions that have already occurred, the researcher
cannot manipulate or change the already occurred actions or behaviour.
3) The research focuses on the effects
Since the researcher tries to analyse and predict the reasons behind the occurrence of an event or phenomena, their first attempt is to focus
on the event or the phenomena that has already occurred. Only after having a detailed study of the phenomena or the event, the researcher
tries to determine the causes behind such an event or phenomena.
4) The research tries to analyse the ‘how’ and ‘what’ aspect of an event
Since the researcher tries to understand the causal effects behind a phenomena, the research basically focuses on how and wha t reasons that
has led that phenomena to occur.
5) Explores possible effects and causes
With the help of an ex-post facto research, the researcher tries to analyse the cause and effect phenomena of an event, action or behaviour.
6.3.) Differences between an Experimental and an Ex-post Facto Research
Research
Experimental research
Ex-post facto research
Control over independent Variable
In an experimental research, the researcher can
directly manipulate the independent variable/s
in orde r to examine its effect on the d ependent
variable.
In an ex-post facto research, the researcher can
not directly manipulate the independent
variable/s on basis of the dependent variable.
Principle of randomisation
The researcher can use the principle of
randomisation in an experimental research on
basis of which they can conclude or infer that
other things remaining equal, constant,
controlled.
The researcher cannot use the principle of
randomisation in an ex-post facto research as
the researcher has no direct control over the
cause and the possibilities of the causes.
Manipulation of variables
The researcher can manipulate variables in an
experimental research
The researcher cannot manipulate variables in
an expost facto research
Interpretation
It is easier to interpret or infer relationships
between the independent and dependent
variables
It is difficult to interpret or infer relationship
between the independent and dependent
variables.
