Intro to Data Scaling and Normalization in Python

Sean Knight
3 min readFeb 28, 2023
Photo by Thought Catalog on Unsplash

If you’re looking to dive into the world of data analysis and machine learning, you’ve probably heard the terms “data scaling” and “normalization” thrown around quite a bit. But what do they really mean, and how can you implement them in Python? Let’s explore.

First off, what is data scaling? Simply put, data scaling is the process of transforming your data so that it fits within a specific range.

Why is this important? Well, many machine learning algorithms require that data be on a similar scale in order to function properly. For example, let’s say you’re working with a dataset that contains both height (in meters or feet) and weight (in pounds) of individuals. If you don’t scale this data, the weight variable will be much larger than the height variable, which could cause issues when trying to build a predictive model.

So, how do we go about scaling our data in Python? One common method is called “min-max scaling.” This involves scaling the data so that it falls within a specified range, usually between 0 and 1. We can use the Scikit-Learn library to easily implement this. Here’s an example:

from sklearn.preprocessing import MinMaxScaler
scaler = MinMaxScaler()
scaled_data = scaler.fit_transform(your_data)

In the code above, we first import the MinMaxScaler class from Scikit-Learn. We then create an instance of this class and apply it to our data using the fit_transform method.

Another scaling method that’s commonly used is called “standardization.” With standardization, we transform the data so that it has a mean of 0 and a standard deviation of 1. This can be useful when dealing with data that has a large range of values. Here’s an example of how to implement standardization in Python:

from sklearn.preprocessing import StandardScaler
scaler = StandardScaler()
scaled_data = scaler.fit_transform(your_data)

In this case, we’re using the StandardScaler class from Scikit-Learn to standardize our data.

Now, let’s talk about normalization. While scaling focuses on changing the range of the data, normalization involves changing the shape of the distribution. Specifically, we transform the data so that it has a mean of 0 and a standard…