Hey, I'm Tomi Mester. This is my data blog, where I give you a sneak peek into online data analysts' best practices. You will find articles and videos about data analysis, AB-testing, research, data science and more…

I put together a ‘Python 3 for Data Science’ tutorial series starting from the very basics. It features 9 practical articles – that covers everything you need to know!

Why are people losing at the casinos? Why shouldn’t you buy a lottery ticket? How do you account for uncertainty when you invest a smaller or bigger amount…

Tomi Gelo was one of the first participants in my 6-week data science course (the Junior Data Scientist’s First Month). Since then, he has done some pretty cool…

One of the most common questions I get from aspiring/junior data scientists is this: Is it possible to get freelance gigs and jobs as a junior data scientist?…

I’ve written about the importance of scripting in data science. But I’ve realized that I’ve never introduced my favorite script editor. It’s Sublime Text 3! In this article,…

Scatter plots are frequently used in data science and machine learning projects. In this pandas tutorial, I’ll show you two simple methods to plot one. Both solutions will…

Google Analytics is the most popular digital analytics tool in the world. Based on W3Techs market share report, Google Analytics is used by 84.1% of all websites for…

Plotting a histogram in Python is easier than you’d think! And in this article, I’ll show you how. I have a strong opinion about visualization in Python, which…

In this tutorial, you’ll learn how to run a Python script. And it’s quite essential. When working on data science projects, you’ll write Python code all the time……

Recently, I had the “pleasure” of setting up my work computer (the computer that I use exclusively for data science projects) from scratch. I have a 2016 Macbook…

Working with current dates and times in data science projects is quite common. In this episode of my SQL tutorial series I’ll show you the best functions that…

In this episode of the SQL tutorial series you’ll learn two simple but important commands that you’ll use frequently when working in SQL: TRUNCATE TABLE and DROP TABLE….

In my previous article about statistical averages, we discussed how you can describe your dataset with a few central values (mean, median and mode). That’s well and good……

I always say that learning linear regression in Python is the best first step towards machine learning. Linear regression is simple and easy to understand even if you…

In this article I’ll answer a very simple question: What is data science? Well, the question is simple, sure… But the answer is rather complex. The problem is…

In my previous landing page A/B test case study, I promised to get back to you with a few A/B testing misconceptions. In this article, I’ll share three…