<h1 id="heading-what-is-the-augmented-dickey-fuller-test">What is the Augmented Dickey-Fuller Test?</h1>
<h3 id="heading-the-dickey-fuller-test">The Dickey-Fuller test:</h3>
<ul>
<li><strong>It is one of the most popular statistical tests. It is used to determine the presence of unit roots in a series and hence helps us to understand if the series is stationary or not.</strong></li>
</ul>
<p>The null and alternate hypothesis for this test is:</p>
<ol>
<li><p><strong>Null Hypothesis</strong>: The series has a unit root (value of a =1)</p>
</li>
<li><p><strong>Alternate Hypothesis</strong>: The series has no unit root.</p>
</li>
</ol>
<ul>
<li><p>If we fail to reject the null hypothesis, we can say that the series is non-stationary.</p>
</li>
<li><p>This means that the series can be linear or difference stationary.</p>
</li>
</ul>
<p><img src="https://cdn.hashnode.com/res/hashnode/image/upload/v1675581412244/c1a4526c-b4ff-4792-86e0-23e1db97e60f.png" alt class="image--center mx-auto" /></p>


# What is the Augmented Dickey-Fuller Test?

### The Dickey-Fuller test:

* **It is one of the most popular statistical tests. It is used to determine the presence of unit roots in a series and hence helps us to understand if the series is stationary or not.**
    

The null and alternate hypothesis for this test is:

1. **Null Hypothesis**: The series has a unit root (value of a =1)
    
2. **Alternate Hypothesis**: The series has no unit root.
    

* If we fail to reject the null hypothesis, we can say that the series is non-stationary.
    
* This means that the series can be linear or difference stationary.
    

![](https://cdn.hashnode.com/res/hashnode/image/upload/v1675581412244/c1a4526c-b4ff-4792-86e0-23e1db97e60f.png align="center")

#98 Machine Learning & Data Science Challenge 98

A Mountain Hiker, Space, and Tech Enthusiast who became a Data Scientist.
