Calculating Entropy with SciPy
SciPy, provides an effecient way for calculating entropy using the “entropy" function from “scipy.stats module“. This function calculates the Shannon entropy of a given probability distribution.
Setting Up your Environment
Before importing, and proceeding further, first we need to install the scipy package.
!pip install scipy
Computing Entropy using scipy.stats.entropy
In the example, we define a probability distribution p and compute the entropy using the entropy function with scipy stats entropy. The base parameter is set to 2, which means the entropy is calculated in bits. Distribution of data among all the classes is maximized when entropy is highest and when all feature samples belong to the same class, the entropy is lowest. An entropy of zero is obtained for a totally homogeneous dataset (when all instances belong to the same class). Generally, Entropy values range from 0 to 1, where:
- 0: represents a perfectly pure dataset (no uncertainty)
- 1: represents a perfectly random dataset (maximum uncertainty)
from scipy.stats import entropy
p = [0.4, 0.3, 0.3] # probability distribution
ent = entropy(p, base=2)
print("Entropy:", ent)
Output:
Entropy: 1.570950594454669
In the example above, the entropy value for 1.57, indicates a level of high uncertainty and random dataset.
How to Compute Entropy using SciPy?
Entropy is a fundamental concept in measuring the uncertainty or randomness in a dataset. Entropy plays a very significant role in machine learning models such as decision trees, helping to decide how best to partition input at each node. Even for those who are not very knowledgeable in the underlying mathematics, the Scipy library for Python, provides features that make computing entropy simple.
In this post, we will understand how to compute entropy using Popular python’s library scipy.
How to Compute Entropy using SciPy?
- What is Entropy?
- Why Compute Entropy?
- Calculating Entropy with SciPy
- Entropy Calculation for Binary Classification using Scipy
- Entropy Calculation for Multi-Class Classification using Scipy
- Conclusion
- How to Compute Entropy using SciPy?- FAQs