Statistics Made Easy

## How to Write a Null Hypothesis (5 Examples)

H 0 (Null Hypothesis): Population parameter =, ≤, ≥ some value

H A (Alternative Hypothesis): Population parameter <, >, ≠ some value

Note that the null hypothesis always contains the equal sign .

We interpret the hypotheses as follows:

H 0 : μ ≤ 20 (the true mean height of plants is equal to or even less than 20 inches)

H A : μ > 20 (the true mean height of plants is greater than 20 inches)

## Example 1: Weight of Turtles

Here is how to write the null and alternative hypotheses for this scenario:

H 0 : μ = 300 (the true mean weight is equal to 300 pounds)

H A : μ ≠ 300 (the true mean weight is not equal to 300 pounds)

## Example 2: Height of Males

H 0 : μ ≤ 68 (the true mean height is equal to or even less than 68 inches)

H A : μ > 68 (the true mean height is greater than 68 inches)

## Example 3: Graduation Rates

H 0 : p ≥ 0.80 (the true proportion of students who graduate on time is 80% or higher)

H A : μ < 0.80 (the true proportion of students who graduate on time is less than 80%)

## Example 4: Burger Weights

H 0 : μ = 7 (the true mean weight is equal to 7 ounces)

H A : μ ≠ 7 (the true mean weight is not equal to 7 ounces)

## Example 5: Citizen Support

H 0 : p ≥ .30 (the true proportion of citizens who support the law is greater than or equal to 30%)

H A : μ < 0.30 (the true proportion of citizens who support the law is less than 30%)

## Additional Resources

## Published by Zach

Your email address will not be published. Required fields are marked *

## Null Hypothesis Definition and Examples

- Chemical Laws
- Periodic Table
- Projects & Experiments
- Scientific Method
- Biochemistry
- Physical Chemistry
- Medical Chemistry
- Chemistry In Everyday Life
- Famous Chemists
- Activities for Kids
- Abbreviations & Acronyms
- Weather & Climate
- Ph.D., Biomedical Sciences, University of Tennessee at Knoxville
- B.A., Physics and Mathematics, Hastings College

## How to State a Null Hypothesis

This can be written mathematically as: H 1 : μ > 6

In this example, μ is the average.

## Null Hypothesis Examples

## Why Test a Null Hypothesis?

To log in and use all the features of Khan Academy, please enable JavaScript in your browser.

## AP®︎/College Statistics

## Examples of null and alternative hypotheses

- P-values and significance tests
- Comparing P-values to different significance levels
- Estimating a P-value from a simulation
- Using P-values to make conclusions

## Want to join the conversation?

## Video transcript

## Have a language expert improve your writing

Run a free plagiarism check in 10 minutes, generate accurate citations for free.

## How to Write a Strong Hypothesis | Steps & Examples

Published on May 6, 2022 by Shona McCombes . Revised on December 2, 2022.

## Example: Hypothesis

Daily apple consumption leads to fewer doctor’s visits.

## Table of contents

## Variables in hypotheses

Hypotheses propose a relationship between two or more types of variables .

- An independent variable is something the researcher changes or controls.
- A dependent variable is something the researcher observes and measures.

## Step 1. Ask a question

## Step 2. Do some preliminary research

## Step 3. Formulate your hypothesis

## 4. Refine your hypothesis

- The relevant variables
- The specific group being studied
- The predicted outcome of the experiment or analysis

## 5. Phrase your hypothesis in three ways

## 6. Write a null hypothesis

- H 0 : The number of lectures attended by first-year students has no effect on their final exam scores.
- H 1 : The number of lectures attended by first-year students has a positive effect on their final exam scores.

## Receive feedback on language, structure, and formatting

Professional editors proofread and edit your paper by focusing on:

## Cite this Scribbr article

McCombes, S. (2022, December 02). How to Write a Strong Hypothesis | Steps & Examples. Scribbr. Retrieved February 28, 2023, from https://www.scribbr.com/methodology/hypothesis/

## IMAGES

## COMMENTS

We interpret the hypotheses as follows: Null hypothesis: The sample data provides no evidence to support some claim being made by an individual. Alternative hypothesis: The sample data does provide sufficient evidence to support the claim being made by an individual.

There are two ways to state a null hypothesis. One is to state it as a declarative sentence, and the other is to present it as a mathematical statement. For example, say a researcher suspects that exercise is correlated to weight loss, assuming diet remains unchanged.

The null hypothesis is often stated as the assumption that there is no change, no difference between two groups, or no relationship between two variables. The alternative hypothesis, on the other hand, is the statement that there is a change, difference, or relationship.

The null hypothesis is the default position that there is no association between the variables. The null hypothesis is written as H 0, while the alternative hypothesis is H 1 or H a. H0: The number of lectures attended by first-year students has no effect on their final exam scores.