Research design is a blueprint for data collection, measurement, and analysis, addressing key questions about the research's purpose and significance. It includes various classifications, levels, and types of designs, such as exploratory, descriptive, and causal research, and emphasizes the importance of minimizing bias and understanding variables. The document outlines foundational concepts like independent and dependent variables, hypothesis testing, and principles of experimental design.

1. Research Design

2. • Def: Research Design constitutes the
Blueprint for the collection , measurement
and analysis of data.
(or)
• Research Design is the plan and structure of
investigation .

3. The Research plan should be written
to address the following questions:-
• What do you intend to do?
• Why is the work important?
• What has already been done?
• How are you going to do the work?

4. • Researcher should know the Background and
significance of the research problem including
proposed rational, current state of knowledge
and potential contributions and important of
the research to the field.
• Literature review is very important. Critically
evaluate existing knowledge, including
background literature and relevant data.

5. Classification of the research design
A number of different design approaches exist, but,
unfortunately. No simple classification systems defines
all the variations that may be considered
• They may be --- Exploratory ,formal study
• Monitoring , communication study
• Experimental , Ex-post-facto study
• Descriptive , causal study
• Cross sectional, longitudinal study
• Case study, statistical study
• Field setting, laboratory research, simulation study.

6. Levels of Research Design
There are four levels of Research design.
they are
1. Sampling design
2. Observational design
3. Statistical design
4. Operational design

7. • SAMPLING DESIGN: The sample design which deals with
the method of selecting items to be observed for the given
study
• OBESERVATIONAL DESIGN : Observational deals which
relates to the conditions under which the observations are
to be made.
• STASTICAL DESIGN : Statistical design which concerns with
the question of how many items are to be observed and
how the information and data gathered are to be analyzed
• OPERATIONAL DESIGN : Operational design which deals
with the techniques by which the procedures specified in
the sampling , statistical and observational design can be
carried out.

8. Features of Good Design
• The design which Minimizes Bias and Maximizes the reliability of
the data collected and analyzed is considered a good design.
• The question of Good Design is related to the purpose of the
research problem and also with the nature of the problem to be
studied.
• A researcher design appropriate for a particular research problem,
usually involves the consideration of the following factors.
1. Obtaining the information.
2. Availability of Staff members and their skills
3. Objective of the problem to be studied.
4. Nature of the problem to be studied.
5. Availability of time and money for the research work.

9. Important concepts relating to research
design :
Before describing the different research
design, first to explain the various concepts
relating to designs. So that there may be
better and easily understood.

10. Dependent and Independent variable
Variable: A concept which can take on different quantitative values is
called a variable.
Ex: like weight, height, income etc .
Variable can be classified into two types: Independent
variable, dependent variable
Independent variable: A Variable which taken individually is called
independent variable.
Dependent variable: A Variable which is depends upon another
variable
Discrete variable: A variable for which the individual values fall on the
scale only with distinct gaps is called a Discrete variable.
Continuous variable : A Continuous variable is that which can assume
any numerical value within a specific range

11. Extraneous Variable
Independent variables that are not related to the
purpose of the study, but may affected the dependent
variables are termed as extraneous variables.
Example: The researcher wants to test the hypothesis
that there is a relationship between children’s gains in
social studies achievement and their self-concepts.
Here self-concept is the independent variable and
social studies achievement is dependent variable. But
Intelligence may as well affect the social studies
achievement, but since it is not related to the purpose
of the study undertaken by the researcher

12. Control
To minimize the influence of
extraneous variables.

13. Confounded relationship
The relationship between the
independent and dependent variables is called
confounded relationship.

14. Research hypothesis
finding the relationship between the
two variables is called research hypothesis.

15. Experimental hypothesis testing
The independent variable is
manipulated is called experimental hypothesis
testing.

16. Non-Experimental hypothesis-testing
The independent variable is not
manipulated is called non experimental
hypothesis-testing.

17. Experimental and Control groups
--- When a group is exposed to usual
conditions is called control group.
--- When a group is exposed to special
conditions is called experimental group.

18. Treatments
The different conditions under which
experimental and control groups are put then
it is called treatments

19. Experiment
The process of examining the truth
of a statistical hypothesis, relating to some
research problem is known as experiment

20. Experimental units
The pre-determined plots (or)
Blocks where treatments are used are known
as experimental units.

21. Types of research designs
There are mainly four types of research designs:
• Research design in case of Exploratory or
Formulative research studies.
• Research design in case of Descriptive and
Diagnostic research studies.
• Research design in case of Hypothesis-testing
research studies.
• Research design in case of Causal research
studies.

22. Research design in case of
Exploratory or Formulative research
studies
To gain familiarity with a phenomenon or
to achieve new insights into it.

23. Research design in case of Descriptive
& Diagnostic research studies
To portray accurately the characteristics of
a particular individuals, situation or a group is
called descriptive research studies.
To determine the frequency with
something occurs or with which it is
associated with something else are called
diagnostic research studies.

24. Research design in case of Hypothesis
– testing research studies
To test a hypothesis of causal difference
between variables.

25. Research Design in case of causal
research studies
To find the relationships between the
variables in the causal form is called causal
research studies

26. Difference between Exploratory or Formulative and
Descriptive / Diagnostic
Research Design Exploratory (or)
formulative
Descriptive /
Diagnostic
Overall design It is a flexible design It is a not flexible Design
1. Sampling design Non-probability sampling
design ( Judgment sampling)
Probability sampling design
(Simple random sampling)
2. Stastical design No pre-planned design for
analysis
Pre-planned design for
analysis
3. Observational design Unstructured instruments for
collection of data
Structured instruments for
collection of data
4. Operational design No fixed Decisions about the
operational procedures
Advanced decisions about
operational procedure

27. Experimental Research
• Experimental are studies involving intervention by
the researcher beyond that required for
measurement. The usual intervention is to
manipulate some variables in a setting and observe
how it affects the subjects being studied.
• The researcher manipulates the independents or
exploratory variables and then observes whether
the hypothesized. Dependent variables is affected by
the intervention

28. Basic principles of experimental designs
Professor Fisher has enumerated Three
principles:
• Principle of REPLICATION.
• Principle of RANDOMIZATION.
• Principle of LOCAL CONTROL of experimental
designs

29. Principle of REPLICATION
According to the principle of Replication
the experiment should be repeated more than
once.

30. Principle of RANDOMIZATION
It Provides the protection,
when we conduct an experiment
against the effect of extraneous
factors by randomization.

31. Principle of LOCAL CONTROL
The Principle of Local control is
another important principle of experimental
design