What is a hypothesis?


It’s a provisional explanation of the research problem or can also be said as a possible outcome of a research. Now, this possibility is found by the assumption made on the basis of various proof or evidence.

A hypothesis is stated before the research is conducted as it states what is considered to be investigated.

Key features of hypothesis

  • Point out the research objectives
  • Find key concepts involved  in the research
  • Identify the relationship between both the problem statement and literature review.
  • A problem must be reduced to hypothesis form to solve it scientifically 
  • It can be testified and stated as verified as well as false
  • These are neither moral nor ethical questions
  • It’s neither too specific nor two general
  • Can also be termed as a prediction of consequences

Importance of hypothesis:

  • Hypothesis eases the extension of knowledge in a sector. They provide a provisional explanation by assumption on the basis of facts and phenomena, which can be tested and validated. It helps in sharpening the region of investigation, which is quite helpful for the investigators for research vastly linked with various things. 
  •  The hypothesis provides the purpose of the study to explore some areas more thoroughly. A specific hypothesis enlightens a researcher to think about the situation which is relevant to the problem at hand.
  • Hypothesis gives researchers some logical statements systematically that consist of certain points in a logical order. It explains the fact that is yet not confirmed. Hypothesis works as a bridge between, known facts and intellectual guessed about an unknown condition. It guides a resemblance to the way of discovery.
  • Hypothesis cuts short the unnecessary, irrelevant fact collection. It mentors a researcher for specifying regarding any experiment. Hypothesis provides a base for sampling and preparing research methodology.
  • Hypothesis implicit the statistical analysis of the data. It brings out the relationship between the tested variables. Hypothesis delimits the study in scope.
  • Hypothesis helps drawing the conclusion of the experiment

Thus Hypothesis plays an important role in setting up research methodology.


Anything that’s not constant is a variable, for example, age can be taken as a variable as the age for a person can be different at different points in time.

Researchers choose certain variables to study since they are suspected to be related to a possible relationship to be discovered. Hence it’s necessary to have a conception of variables and their types to further study on types of hypotheses.

There are two main type of variables Independent and dependent variables.

Independent variable

Variables that can be controlled, selected, or changed are independent variables, also called manipulated variables. Now why it’s called Independent, not because it’s independent of any manipulation, it’s called so because it is isolated from any other factor. The Independent variable is also responsible for some changes in other variables.

Example – for dependent variable

Dependent variable

The dependent variable is the variable being tested and measured in an experiment it can only change by the influence of the independent variable that is any change in dependent variable is caused due to the independent variable or in simple terms dependent variable is dependent on the independent variable.

An example of a dependent variable is depression symptoms, which depend on the therapy type which is an independent variable.

                                                            Types of Hypothesis

Simple hypothesis

It’s the prediction of the relationship between a dependent variable and a single independent variable.

Example- Smoking leads to cancer, here smoking is an independent variable due to which results in cancer (dependent variable).

Complex hypothesis

It predicts the relationship between the dependent variable and two or more independent variables.

Example- use of fertilizers, improved seeds, and modern equipment leads to high agricultural productivity.

Directional hypothesis

Are the assumption deduced from theory, data of some previous study, or any other data or evidence which specifies the relationship between variables in a direction, which helps researchers to investigate more deeply in a direction rather than investigating a vast area?

Non directional Hypothesis

Are the assumption made when there is no theory, no strong evidence neither findings of the previous study are contradictory Thus it may not define the relationship between the variables thus unable to direct the investigation in a particular direction. Hence non-directional hypothesis.

Associative hypothesis

In these kinds of hypotheses when related variables are changed it doesn’t cause any effect.

Causal hypothesis

In this kind of hypothesis relation between variables gets effected if the independent variable is changed or manipulated.

Null hypothesis

States that there is no relationship between variables, the theory stated by the null hypothesis is not stated on the basis of any evidence or proper theory rather these are the beliefs of researchers. These kinds of hypotheses are used when there is a lack of proper proofs, evidence, or any sort of strong leadership. Hence in these cases, decisions must be taken carefully to avoid some serious outcomes. Designated by- Ho or H0

Null hypothesis can

  • Simple as well as complex
  • Associative as well as causal

Alternative hypothesis

It states the relationship between two variables. In simple terms, it’s the opposite of the null hypothesis.

Designated by Ha or H1. It is accepted after Null hypothesis is rejected.

As it has been stated earlier an alternative hypothesis is taken into consideration only when the null hypothesis is rejected thus this implies the null hypothesis special importance. I.e. ‘reject Ho in favor of Ha’ or ‘do not reject Ho’.

Now why null hypothesis is taken in first priority?

“Do not reject H0” we conclude so because “do not reject H0” does not necessarily mean null hypothesis is true, it rather suggests there is not enough evidence against H0 in favor of Ha, and “reject Ho in favor of Ha” suggests alternative hypothesis may be true.

For example:

Ha= the males visited Bar more than females.

Ho= the males and females do not differ with respect to the frequency of going to the bar. So, the Alternative hypothesis is usually the one which one wishes to prove and the Null

Hypothesis is the one which one wishes to disapprove.

Characteristics of good hypothesis:
  • It must be simple so that it is understandable to everyone
  • The assumption should be made on basis of as much as possible strong evidence, proofs, etc.
  • The hypothesis should be able to direct researchers in a particular direction so that they explore a small and accurate area needed for the research rather than exploring unnecessary areas.
  • A hypothesis must have the capability of being experimented with or tested.
  • It must have a proper relationship between variables.