The document discusses hypothesis, null hypothesis, and alternative hypothesis in research methodology. It defines a hypothesis as a tentative explanation for a problem being investigated. A null hypothesis proposes that there is no relationship between two variables, while an alternative hypothesis proposes there is a relationship. The researcher aims to disprove the null hypothesis and prove the alternative. Statistical hypothesis testing involves stating the hypotheses, developing a test plan, analyzing sample data, and determining whether to reject or accept the null hypothesis based on the results and significance level.

1. Research Hypothesis

2. Two of four stages in application of
scientific method in research
methodology are
• Formulating Hypothesis
• Testing hypothesis

3. • It is very essential for the scientist
to understand the meaning and
nature of hypothesis.
• Hypothesis need to be clear,
precise and capable of being
tested.
Hypothesis

4. Hypothesis
• Hypothesis is a tentative solution of a
problem.
• It is an important part of scientific
research.
• Aim to make predictions about some
outcome.

5. Example
• The researcher is investigating the history of a
village which not have basis for making
prediction .
• Hypothesis is not required in such fact finding
studies.
• The amount of quality and evidence
determine the hypothesis.

6. Null hypothesis
Hypothesis shows there is
no statistical significance
between two variables in
the hypothesis.

7. Non directional hypothesis.
No relationship between
two variables.
Null hypothesis

8. Academic performance of college
student who participate in sports.
Academic performance of college
student who non-participate in
sports.
Null hypothesis

9. • If it is tested statistically then it is
called statistical hypothesis.
• Researcher must remain unbiased
throughout the study.
• It is the hypothesis that the
researcher tries to disprove.
Null hypothesis

10. Example 1 : If the hypothesis is that
the consumption of a particular
medicine reduces the chances of heart
arrest.
The null hypothesis will be “ the
consumption of the medicine does not
reduce the chances of heart arrest.

11. Example 2: random test
scores collected from
men differ from women
The null hypothesis will be the
mean test score of men is same
as that of the women.

12. Statistical hypothesis are tested using
four step process.
• First step : The analyst to state the two
hypotheses so that one can be right.
• Second step: Formulate the analysis plan
which outlines how the data will be evaluated.
• Third step: carry out the plan and physically
analyse the sample data.
• Fourth step: Analyse the results and reject or
accept the null hypothesis.

13. In studies where the collected data
does not complete the expectation of
null hypothesis, it is concluded that
the data does not provide sufficient or
reliable pieces of evidence to support
the null hypothesis and thus it is
rejected.

14. Alternative hypothesis
• It defines there is a statistically
important relationship between two
variables.
• It reflects that there will be an
observed effect for our experiment.
• It is contradictory to the null
hypothesis

15. For example the null hypothesis
might be “ there was no change in
the water level this spring.
The alternative hypothesis
would be “ there was a change
in the water level this spring.”

16. • The hypothesis is to be proved that
indicates that the results of the study is
significant.
• The sample observation is not result just
from chance but from some non random
cause.
• It is a hypothesis that the researcher tries
to prove.
Alternative hypothesis

17. The null hypothesis for all the three alternative
hypothesis, would be
If the null hypothesis is rejected then we accept
the alternative hypothesis.
If the null hypothesis is not rejected, then we do
not accept the alternative hypothesis.
Alternative hypothesis

18. Three types of alternative hypothesis
•Left tailed
•Right tailed
•Two tailed

19. One tail - Left tail test Left tailed :
sample proportion[ μ1] is less than a
specified value denoted by [μ2]
H1: μ1 < μ2

20. One tail – Right Tail test
Right tailed: sample proportion is
greater than some value H1: μ1 > μ2

21. Two tail or non directional test
Two tailed: sample proportion is not
equal to a specific value

22. Difference between null hypothesis
and alternative hypothesis
Null hypothesis Alternative hypothesis
There is no relationship /
association ship between two
groups .
There is a relationship between
two selected variables in a
study.
It is denoted by H0 It is denoted by H1 or H2
It is followed by ‘equal to ‘ sign It is followed by not equal to,
‘less than ‘or ‘greater than’ sign
The researcher tries to disprove
in null hypothesis
The researcher tries to prove in
alternative hypothesis

23. Difference between null hypothesis
and alternative hypothesis
Null hypothesis Alternative hypothesis
The results are observed as a result of
chance
The results are observed as a result of
some real causes
The result of null hypothesis indicates
no changes in opinions or actions
The results of an alternative
hypothesis causes change in opinions
and actions
If the null hypothesis is accepted the
results of the study become
insignificant
If an alternative hypothesis is
accepted the results of the study
become significant
If the P value is greater than the level
of significance, the null hypothesis is
accepted
If the P value is smaller than the level
of significance an alternative
hypothesis is accepted

24. Hypothesis testing
• It is a process of deciding statistically whether
the findings are real or chance.
• Research in which the independent variable is
manipulated is called experimental hypothesis
testing research.
• A research in which an independent variable is
not manipulated is called non experimental
hypothesis testing research.

25. • The use of null hypothesis is quite frequent.
• If the significance level is 5 % it means that the
researcher is ready to take 5% risk to reject
the null hypothesis when it happens to be
true.
• P value is used as an alternative to rejection
points to provide the smallest level of
significance at which the null hypothesis
would be rejected.

26. Procedure for testing hypothesis
State null and
alternate hypothesis
Select level of
significance
Identify the test
statistics

27. Procedure for testing hypothesis
Formulation a decision
rule
Take a sample arrive at
decision
Do not reject Ho
Reject Ho
Accept H1