The Art of NFL Ranking, the ELO Algorithm and FiveThirtyEight


In this blog, I will focus on the NFL Ranking based on the ELO algorithm that Nate Silver’s FiveThirtyeight uses. The guys at 538 have done a good job.The ELO and NFL ranking was part of my workshop at the Global Big Data Conference this Sunday. The full presentation is in slideshare


ELO – the algorithm made famous by Facebook & depicted in the movie Social Network

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 Basic ELO

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The k-Factor is the main leverage point to customize the algorithm for different domains.

  • For example Chess has no notion of a season; Soccer,Football & Basket ball are dependent on seasons – teams change during different seasons
  • Chess has no score to consider except WIn,Lose or Draw; but ball games have scores that need to be accommodated
  • For Chess k=10; for soccer it varies from 20 to 60; 20 for friendly matches to 60 for World Cup Finals
  • As we will see later, NFL adjusts k with the Margin Of Victory Multiplier
  • NFL also adjusts k to weigh recent games more heavily, w/ exponential decay
  • There are also mechanisms for weighing playoffs higher than regular season games (We will see this in Basketball)

538’s take on ELO

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NFL 2014 Predicts & Results

The R program ELO-538.R is in Github

2014 Ranking Table

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To Do

  1. Exponential decay with more weight for recent games – later in the season
  2. Calculate the rankings from 1940 to present, draw graphs like this from 538

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2 thoughts on “The Art of NFL Ranking, the ELO Algorithm and FiveThirtyEight

  1. Pingback: Take Care of the Ball, Value every Possession & Protect the Rim | My missives

  2. Pingback: An excursion into ranking the NBA with Elo | My missives

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