Learn the difference between PCA and Factor Analysis — and when to use which — with Python and R example code

What is the difference between PCA and Factor Analysis?
What is the difference between PCA and Factor Analysis?
What is the difference between PCA and Factor Analysis? Photo by Austin Distel on Unsplash.

PCA, short for Principal Component Analysis, and Factor Analysis, are two statistical methods that are often covered together in classes on Multivariate Statistics.

In this article, you will discover the mathematical and practical differences between the two methods.

Multivariate Statistics — Reducing the number of variables

Multivariate Statistics is a group of statistical methods that focus on studying multiple variables together while focusing on the variation that those variables have in common.

Its goals are therefore different from supervised modeling, but also different from segmentation and clustering models.

There are many models in…


Hands-on Tutorials

Adding API tokens to an AWS API for access management

How to add API Keys to Your AWS API Gateway API?
How to add API Keys to Your AWS API Gateway API?
How to add API Keys to Your AWS API Gateway API? Photo by Glenn Carstens-Peters on Unsplash.

In this article, I will explain how to add a basic security level to APIs that have been made using AWS API Gateway. This will be done through adding tokens.

Tokens are codes that you need to send with an API request, and that work more or less like a password. If your token allows you to access the data, the API will send you the data. Else it will send you an error.

To follow alongwith the example, you can use the AWS API Gateway API made in this previous article, which send back a randomly generated password. …


A Full Guide to Waiting Line Models and Queuing Theory

Waiting line models. Photo by Halacious on Unsplash

In this article, I will give a detailed overview of waiting line models. I will discuss when and how to use waiting line models from a business standpoint. In the second part, I will go in-depth into multiple specific queuing theory models, that can be used for specific waiting lines, as well as other applications of queueing theory.

Introduction to waiting line models

Waiting line models are mathematical models used to study waiting lines. Another name for the domain is queuing theory.

Waiting lines can be set up in many ways. In a theme park ride, you generally have one line. In the supermarket, you…


The Full Guide to Getting Started with Machine Learning in Julia

Machine Learning in Julia
Machine Learning in Julia
Photo by Kevin Ku on Unsplash

What is Julia?

Julia is a relatively new programming language that has been gaining traction in the Machine Learning world. As it is getting more and more popular, I wanted to do this article to give you an in-depth overview of why and how to get started with Machine Learning in Julia.


How to set up and train a Yolo v5 Object Detection model?

Yolo v5 Object Detection Tutorial
Yolo v5 Object Detection Tutorial
Yolo v5 Object Detection Tutorial. Photo by Stefan Cosma on Unsplash

Object Detection is a task in Artificial Intelligence that focuses on detecting objects in images. Yolo V5 is one of the best available models for Object Detection at the moment. The great thing about this Deep Neural Network is that it is very easy to retrain the network on your own custom dataset.

In this article, I will cover how to train a Yolo V5 Object Detection model. I will focus on how to get started quickly and easily, rather than on tuning the hyper parameters of the model.


Intuitive explanations for the Normal, Bernoulli, Binomial, Poisson, Exponential, Gamma and Weibull distribution — with Python example code

7 Statistical Distributions that every Data Scientist should know
7 Statistical Distributions that every Data Scientist should know
7 Statistical Distributions that every Data Scientist should know. Photo by Luke Chesser on Unsplash.

Statistical Distributions are an important tool in data science. A distribution helps us to understand a variable by giving us an idea of the values that the variable is most likely to obtain.

Besides, when knowing the distribution of a variable, we can do all sorts of probability calculations, to compute probabilities of certain situations occurring.

In this article, I share 7 Statistical Distributions with intuitive examples that often occur in real-life data.

1. Normal or Gaussian distribution

The Normal or Gaussian distribution is arguably the most famous distribution, as it occurs in many natural situations.

A variable with a normal distribution has an average…


Because APIs are the future!

How to build an API in AWS — using Lambda and API Gateway
How to build an API in AWS — using Lambda and API Gateway
How to build an API in AWS — using Lambda and API Gateway. Photo by Emile Perron on Unsplash

APIs, short for Application Programming Interfaces, are connection points that allow different (parts of) computer programs to exchange data. Using APIs for the delivery of a software service makes your code better organized and easily reusable.

In this article, I am going through the basic steps of creating an API using AWS Lambda and API Gateway.

The example is a very short code example, that will create a random password, based on a given length, a number of capitals, and a number of numerical characters. The other characters will be small letters. …


The Easiest Object Detection Tutorial Ever — Using YoloV5 and Python

Source. Creative Commons Attribution 4.0 International. Adaptations by author.

In this article, I will give the steps to get started using YoloV5 for object detection. The goal of object detection is to draw bounding boxes on objects on images. YoloV5 is (one of) the best tools to do this with a small amount of work.

The YoloV5 model has been pre-trained. We can choose to train it further, but in this article, I will show how to use YoloV5 out-of-the-box.

You can find the full notebook over here in case you want to follow along.

1. Install YoloV5

The following block of code will download the pre-trained YoloV5 model to your computer.


All you need to know on the PSM 1 Scrum certification!

Is a PSM 1 — Scrum Master certification worth it?
Is a PSM 1 — Scrum Master certification worth it?
Is a PSM 1 — Scrum Master certification worth it? Photo by Chichi Onyekanne on Unsplash.

Agile methods are getting very common in the workplace, especially in technology-oriented teams and companies. Scrum is one of the most famous approaches for doing Agile work. According to the official definition:

What is Scrum really about?

Scrum is about working in an iterative way, meaning that you start with a very small product, and then in each fixed period called a sprint (often three weeks) you build an increment (an additional feature) for this product.


Don’t replace but repair: save the environment and your wallet!

Not this old of course. Source. © Bill Bertram 2006, CC-BY-2.5 — Attribution.

Computers on the market are continuously getting more and more powerful. So older computers cannot be expected to have top-notch performances.

However, small tweaks to an older machine can make that they are still perfectly useable by someone with small needs. For example for an elderly person using his computer only or email, or a student only in need of writing their thesis.

Recycling your old computer is great for the environment and it will be much cheaper than buying a new low-performance computer!

Problems on old computers and their solutions

1. Slow computing speed — the blocking point

CPU power is strongly increasing over time. You often have a sticker on your computer saying…

Joos Korstanje

Data Scientist — Machine Learning — R, Python, AWS, SQL

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