This document discusses hypotheses and types of variables in research. It defines a hypothesis as a conjectural statement about the relationship between two or more variables. A hypothesis guides research and can be tested. The document outlines null and alternative hypotheses and discusses types of variables such as independent, dependent, intervening, stimulus, response, quantitative, qualitative, discrete, continuous, dichotomous, and polytomous variables. It provides examples to illustrate each variable type.

1. HYPOTHEIS & TYPES OF
VARIABLES
 PrePared By :
 SONdarVa yaGNeSH
 M.Sc.(aGri) exteNSiON
 1St
SeMeSter
 Baca, aaU, aNaNd

2. Hypothesis
 Webster: “ Hypothesis is a proposition
or condition or principle which is
assumed in order to draw out its logical
consequences and by this method, to
test its accord with facts which are
known or may be determined.”
 Lundberg: “Hypothesis is a hunch,
guess or imaginative idea which
becomes the basis for action or
investigation.”

3. Hypothesis
 Kerlinger: “Hypothesis is a conjectural
statement of the relation between two
or more variables.”
 Black: “ Hypothesis is a proposition not
known to be definitely true or false,
examined for the sake of determining
the consequences which would follow
from its truth.”

4. Theory and Hypothesis
 Theory is used to denote a hypothesis that is
almost completely established and well on the
way towards becoming a law.
 According to Webster: “A hypothesis is a
propositional conjecture as to causes or
relations of phenomenon, while a theory is a
verified hypothesis applicable to many related
phenomenon.”
 Thus, scientific march of a hypothesis leads
towards theory.

5. Characteristics of a good
hypothesis
 Clear, specific and limited in scope
 Simply stated
 Consistent with the relevant objectives of
research
 Capable of being tested and related to
available techniques
 Not include value judgments, relative terms or
any moral teaching
 State the relationship between variables, if the
study is designed for that

6. Sources of hypothesis
 Experience of researcher
 Review of literature
 Findings of the pilot study
 Interaction with knowledgeable persons of
the concerned field
 Knowledge of culture and society
 Creative thinking and imagination of
researcher

7. Utility of hypothesis
 It acts as a guide- a sort of guiding light in the
journey of research.
 It prevents blind research. It spells out the
difference between fruitful and fruitless
research.
 It provides direction to research, identifying
what is relevant and what is irrelevant.
 It serves as a framework for drawing
meaningful conclusions.

8. Types of hypothesis

Null Hypothesis (Ho):
It is the hypothesis which is set for possible rejection
under the assumption that it is true. It is the hypothesis
of no difference. It states that there is no difference
between the population under study.
It is like the legal principle that a person is innocent
until proved guilty. It constitute a challenge and the
function of a researcher is to give the facts a chance
to refute this challenge.
Ho : The males and females do not differ significantly
in respect of their frequency of televiewing.

9.  Alternative Hypothesis (H1)
It is one which is set for possible acceptance or
possible inequality. It is a complementary
statement to the null hypothesis. It is very
important to state the alternative hypothesis
explicitly, because rejection of null hypothesis
implies acceptance of alternative hypothesis
and vice-versa.
H1 :The females watch television significantly
more than the males

10. Level of significance
 Since no one is ever certain that the sample
information accurately represents the
population information, researchers specify
the risk of rejecting the null hypothesis when
it is correct. This risk, expressed in terms of
probability, is called the level of significance.
 Two levels of significance are commonly
used:
 0.05 or 5%
 0.01 or 1 %

11. Type I and Type II errors
 Test of significance is the test of
correctness of hypothesis on the basis of
information obtained from the sample.
 In testing the null hypothesis, we may
come across the following alternatives:
1. Ho is correct, test accepts Ho
2. Ho is not correct, test rejects Ho
3. Ho is correct, but test rejects Ho (Type I error)
4. Ho is not correct, but test accepts Ho (Type II error)

12. VARIABLE
 A variable is a characteristic of interest that varies from one item to
another and may take any one of a specified set of values or
attributes.
 It can be defined as any characteristic of an individual or a thing
under study.
 In other words, it means some characteristics of each number of the
unit that is to be studied such as income, age, test score, land
holding, etc.
 Any item or characteristic which can be observed or measured and
whose observation or measurement will be useful for the study can
be regarded as a variable for the study.
 A variable can take on different values for different individuals
 Ex: Heights of individuals: Student #1: 5’ 5” Student #2: 5’ 7”
Student #3: 5’ 2”

13. Types of variables
Variables
Discrete Continuous
Dichotomous Polytomous
Dependant Independent
Intervening
Stimulus Response
Qualitative
Active
Quantitative

14. Types of variables
 Quantitative variable:
It is one which generates numerical values.
For example, consider a study of guests at
a hotel. We may be interested in the age
of a guest, their spend and length of stay.
Each characteristic is a quantitative
variable because the data that each
generates is numerical – for instance, a
guest may be 34 years of age, spend
Rs.500 and stay for seven days.
Quantitative variables generate
quantitative data.

15. Types of variables
 Qualitative variable:
Any variable that cannot be manipulated or at least
is difficult to manipulate is called qualitative variable.
Qualitative variables generate non-numerical or
qualitative data. For instance, ‘nationality of hotel
guest’ is a qualitative variable because nationality
can be classified as British, American, French, etc.
 Active variable:
A variable that is manipulated is called active
variable. e.g. creating anxiety through agricultural
film show, award of prizes etc.

16. Types of variables
 Discrete variable:
It is the one which involves counting the number of
events. It consists of only whole numbers; fractional
values can’t occur.
e.g. the number of inhabitants in a village
 Continuous variable:
They are divisible into smaller and smaller fractional
units. e.g. age of farmer. The characteristic of a
continuous variable is that , within whatever limits its
values may range, any value is possible.

17. Types of variables
 Dichotomous variable:
A variable which has only two values.
e.g. female-male, adopter-non-adopter
 Polytomous variable:
It can have more than two values.
e. g. the influencing skill of extension
worker may be high, some what high,
medium, low etc.

18. Classification of variables
 Independent – This variable is the presumed
cause of the dependent variables
 Dependent – This variable is the presumed effect /
consequences .It is the condition which
the researcher tries to explain.
Effect / consequences
Education Adoption
(independent variables) (dependent variable)

19. Types of variables
 Intervening variable:
According to Kerlinger, “ the constructs, which
are non-observable, are called intervening
variables.” It can neither be seen, nor heard
nor felt. It is inferred from the behavior. e.g.
Hostility is inferred from hostile or aggressive
acts. Motivation can be inferred from
motivated behavior.

20. Types of variables
 Stimulus variable:
It is the condition or manipulation created by
the researcher so as to evoke a response in an
organism. The general class of things that
relate to the environment, situation or
condition of stimulation are referred to as
stimulus variables. e.g. a slide show, a field
day, method demonstration etc.

21. Types of variables
 Response variable:
Any kind of behavior of the respondent is
called response or behavioral variable. This
refers to some action or response of an
individual. It may also refer to the
frequency with which a particular event
occurs or it may be the scale value of a
particular event.
e.g. the response of farmers for questions
like, have you attended the field day?
Yes/No.

22. Types of variables
 Extraneous variable:
Extraneous variables are those variables
that are not related to the purpose of the
study, but may affect the dependent
variable. It is therefore essential that
extraneous variables are controlled.
For example, intelligence may be the
extraneous variable in studying the
efficacy of method of instruction on the
achievement score.