Hands-on Tutorials

Using ARIMA models and the Case-Shiller Index with some creative R programming lets us predict national housing prices for the next year. How can that be?! Let’s find out!

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Photo by Alex Vasey on Unsplash


  1. Predict the next year of US housing prices
  2. Get experience with using real economic data
  3. Visualize the data
  4. Understand underlying assumptions about the data
  5. Learn about predictive modeling using the ARIMA method


This project is designed for two kinds of people — those interested in the code and those interested in the real estate market. While the concepts will be presented with technical definitions and code examples, it will not be necessary to understand the code to learn about cyclical the nature of housing prices, predictive modeling, or economic data.

For those just reading along, try not to get caught up in the code. Look for the images and plots along the way because I will explain as simply as I can in plain English what is happening and why it matters to us. …

Let me share the glory of the full_join() function with you using the R language!

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Photo by Martin W. Kirst on Unsplash

Have you ever been working with multiple tables of data in R and had trouble merging them into a single table? Did you go to Google to tell you to “just use rbind” or see four different ways of joining other people’s data that doesn’t make sense? Well, I have too and so have many of my students.

Here is a concise little guide to how to use rbind, several kinds of joins, and how to resolve common issues when using these functions!

For your convenience, I have made an R Markdown file (.rmd) available on my GitHub at this link if you would rather take a look through the notated code and run it cell by cell or clone it to your machine. …

Learn about the Economics of Equilibrium using R and ggplot2

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Photo by rupixen.com on Unsplash

Welcome to part 3 of the Economics for Tech People series!

This series is intended to help people better understand fundamental principles of economics while also building up skills with the R language. I have noticed there is quite a bit of misunderstanding and outright misinformation about economics, so the goal here is to clear up these fuzzy areas.

In this article, we will explore questions such as: What is equilibrium? How can I find the equilibrium price and quantity? What happens when the numbers do not work out perfectly? How much revenue can I expect to make?

This article assumes that you have a good understanding of both previous parts, which are Economics for Tech People — Demand (Part 1) and Economics for Tech People — Supply (Part 2). Much of the content here builds on code from those two articles as well as explanations of the concepts. Take a look at those before getting started here if you want the full story. …

Learn about the Economics of Demand using R and ggplot2

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Photo by Science in HD on Unsplash

Welcome to part 2 of the Economics for Tech People series!

This project is designed to help people learn about fundamental economics concepts and R programming at the same time. I have noticed there is quite a bit of misunderstanding and outright misinformation about economics, so the goal here is to clear up these fuzzy areas.

What is supply? Who supplies things? What is the difference between quantity supplied and supply? How much should I make of my good or service? How can I figure out the maximum total revenue?

I will be referencing many points of my previous article Economics for Tech People — Demand (Part 1), so make sure you take a look at that before getting started with this project. I will write this article to be a standalone project, but the series will build on itself over time. …

Learn about the Economics of Demand using R and ggplot2

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Photo by Giorgio Trovato on Unsplash

This project exists because I have noticed that there is a tremendous amount of misunderstanding about what the word “demand” actually means in an economic context, especially in the world of technology.

Who demands things? What is a curve? Why does the demand curve change? Why is it wrong to say that a change in price means a change in demand? What is the difference between demand and quantity demanded? What does elasticity even mean? How can I figure out the maximum total revenue?


What we are going to do in this article is explore concepts in demand using R programming to analyze and visualize some realistic data I created in an Excel file. …

Use historical baseball data and logistic regressions with R to predict the number of runs scored in World Series games.

Stadium with a crowd for baseball
Stadium with a crowd for baseball
Photo by Tim Gouw on Unsplash


Have you ever wondered what American baseball, machine learning, and statistics have in common? Well, you’re in luck today!

In this project, we are going to use some freely available historical baseball data with the glm() function in R to see what variables matter in predicting how many home runs happen in games in the World Series.

There are a couple assumptions with this project. First, you have an R environment setup. I am going to be using an R Markdown (RMD) file in RStudio on a Mac for this project, but the code will work on other operating systems and environments just fine. Second, you have at least a rudimentary understanding of baseball. I am by no means an expert about baseball, but there will not be any significant knowledge required. …

What you are really giving up by wasting 3 hours a day on your phone like the average American during your working life.

Man zoning out looking at a smartphone
Man zoning out looking at a smartphone
Photo by Eddy Billard on Unsplash


This article was inspired by my experience of trying something suggested by Anton Kreil in his video “Ditch the Smart Phone” [1]. I respect his idea and do not want to misrepresent his words, so do yourself a favor and watch that video for yourself. Ultimately, the fundamental idea here is that you are better off to get rid of your smartphone in favor of a “dumb phone” that only does text and calls, so you can allocate your time more profitably.

To many people, the idea of getting rid of their smartphone seems preposterous. Well, I tried the idea of not using a smartphone, and it turns out that he is completely right about every point he makes here. …

Take a CompTIA exam, they said. It will be fun, they said.

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Photo by Nick Morrison on Unsplash

Studying the Wrong Material

You do no need to spend thousands of dollars or spend months in a formal class to pass CompTIA exams.

Between the end of April 2019 and the first week of December in 2019 I studied for and passed the A+, Network+, and Security+ while also working on a master’s degree. The only two sources relevant to pass are CompTIA’s Certmaster Practice (have to pay) and ProfessorMesser.com’s free study videos. That is all I used and have had plenty of students pass using only those two sources.

Please do not waste your time and money on secondary sources that are not straight from CompTIA that charge you an arm and a leg for the privilege of learning their interpretation of what is on the exam. CompTIA does not care what they say, so you should not either. The point is to pass the certification not to read a novel about technology. You can do that on your own time. …

Maybe music is the solution to your creative woes.

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Photo by Puk Khantho on Unsplash

How to Know When to Jam

I’ll go out on a limb here. If you’re reading this, you write a lot, code a lot, or do both a lot. Going a bit further, you probably get stuck from time to time. Here’s when I know it’s time to jam.

At this point in my life, writing articles or papers for school feels about the same as writing code for clients or students. I can handle it for a few hours at a time before I need a break. …

Embrace the suck until you get good enough for fun and profit.

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Photo by Soundtrap on Unsplash

Here’s real story without all the “I did it and you can too!” hype thrown in for click bait.

It’s Grueling and Awful for 1–3 Years

Let’s get real. Unless you’re a pre-trained super-intelligent AI or a child savant who is a reincarnated Mozart, you are not going to sit down with an instrument and be great or code the next machine learning breakthrough on day one. It’s going to be real, hard, and real hard to get good enough to make money with either one.

Learning to Play Music

I started seriously learning to play an instrument, alto saxophone, when I was in middle school. When I got it out of the case the first time, I did not even know how to put it together. For the first several weeks and probably months, crude screeching noises, audible cursing, and a general lack of coordinated finger movement were the most common outputs of my early efforts. …


Tyler Harris

I write about technology and business. Working on a PhD in IT. Have a MS in IT & a BS in Economics with CompTIA Security+, Network+, and A+ certifications.

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