ERB Reference Network

tl;dr: I made a network to see if all Epic Rap Battles are connected through references. Surprisingly, most of them are, and the network looks very cool.

Epic Rap Battles of History (ERB for short) is a YouTube music project created by Peter Shukoff and Lloyd Ahlquist in September 2010. Every episode, two (or more) historical and pop culture personalities face off against each other in a rap battle style. Famous episodes include "Adolf Hitler vs. Darth Vader", "Steve Jobs vs. Bill Gates" and "Dr. Seuss vs. William Shakespeare". In its decade-long existence, the series has featured more than 200 characters along its total of 82 episodes, and during that time, it has also aggregated 37 billion views.

During a rap battle, it's common for a character to reference someone. For example, in "Bob Ross vs. Pablo Picasso", Picasso says: "I am the greatest, the modern art Muhammad Ali", which is an explicit reference to the boxer champion Muhammad Ali. This may sound trivial, but I find it interesting because Muhammad Ali appeared as a character in the next battle ("Michael Jordan vs. Muhammad Ali"), creating a nice sense of foreshadowing that I found amusing. However, the really interesting thing to me is that in that following battle, Ali says to Jordan: "When you came back a wizard like Gandalf the Black", which is a reference to Gandalf, that appeared two season back in "Gandalf vs. Dumbledore"!

At some point, I inevitably started to wonder: Are they all connected? Can I get from Picasso to everyone else, using a reference at a time?

To answer that question, I created the network you see in the background. The nodes in the network are characters, and the edges are references. There are three types of references:

  1. Battle: two characters are connected through a battle when they've appeared in the same battle at least once.

  2. Verbal mention: a character A verbally mentions a character B during one of its verses. Ex.: The Joker mentions Stephen King during "The Joker vs. Pennywise", through the verse "You're a sewer troll that Mr. King wrote between his lines!".

  3. Cameo: a character A appears in the background of a character B's verse, or in some cases, during the whole duration of a battle where B is a protagonist. An example would be in "Theodore Roosevelt vs. Winston Churchill": during Churchill's verse "If Rushmore was a band, then you'd play bass!", three previous characters appear: George Washington, Abraham Lincoln and Thomas Jefferson.

Using the above framework as a guide, I watched all 82 Epic Rap Battles (two times each) and pored over them sick lyrics. I also used the Epic Rap Battle Wiki to corroborate some of my annotations. After ~9 hours, the result is what you see on the background. Feel free to close this window and explore the network!

As you can see, there are 16 different connection groups (a.k.a. "weakly connected components"); if everything were connected, there would be only one. This may sound frustrating, but it should be noted that the biggest group contains 164 nodes - which means that approximately 81% of all characters are connected!! This one information, in and of itself, is already very amusing.

With this dataset, many other curious observations can be made:

I think this is an extremely important subject, and more attention should be devoted to scientific research on Epic Rap Battles of History. I invite you to download this dataset and reach your own conclusions: GitHub repository. Have fun!

Last updated: 24-05-2021

Click on the nodes to drag them around.
Click on the edges to watch the segment in question.
LMB to move the camera, mouse wheel to zoom.

Have fun!