Catan ELO Calculator

This is a Python script that takes a csv file of Settlers of Catan games and produces an ELO ranking of the participants.

My friends and I have been playing a lot of Catan online against each other during the covid-19 pandamic rona stay at home order of 2020 via the Catan Classic App doing tournaments and keeping track of various expedition matches.

Here's the spreadsheet we've been using to keep track of our games.

Getting Started

You need Python 3.6+ installed.

Open your favorite command line and run

calculateRanking.py mastersheet.csv

I've provided a sample csv namely mastersheet.csv, but you can use whatever file you want as long as it follows the pattern of mastersheet.csv:

• row 0 : Date,Player 1 name,Player 2 name,Player 3 name...
• row n>0 : <dateOfMatch>,P1 Victory Points,P2 Victory Points,P3 Victory Points...
• For every player that didn't play in the match, give them 0 victory points.

Calculation Details

For each match, each player's new ELO is calculated by summing up the ELO change as if the player was playing a 1v1 match against each of their opponents.

The ELO change is calculated by taking the sum of the following against each of their opponents:

A win status (1 if they have more VPs, 0 if they have less, 0.5 for a tie) minus the ELO probability function (the big funtion with the 10^(ELOdiff/400)) multiplied by a "game importance factor" named K, which is always 30... for now.

K * (winStatus - ELOProbability) 

Example: Player 1 scores 10 VPs, Player 2 scores 8 VPs, Player 3 scores 8 VPs, Player 4 scores 6 VPs.

Player 1's new ELO =

Player 1's old ELO
+ 30 * (1 - ELOProbability(Player 1, Player 2))
+ 30 * ( 1 - ELOProbability(Player 1, Player 3)) 
+ 30 * (1 - ELOProbability(Player 1, Player 4))

Player 2's new ELO =

P2's Old ELO
+ 30 * (0 - ELOProbability(P2, P1))
+ 30 * (0.5 - ELOProbability(P2, P3)) 
+ 30 * (1 - ELOProbability(P2, P4))

Player 3's new ELO =

P3's Old ELO
+ 30 * (0 - ELOProbability(P3, P1))
+ 30 * (0.5 - ELOProbability(P3, P2)) 
+ 30 * (1 - ELOProbability(P3, P4))

Player 4's new ELO =

P4's Old ELO
+ 30 * (0 - ELOProbability(P4, P1))
+ 30 * (0 - ELOProbability(P4, P2)) 
+ 30 * (0 - ELOProbability(P4, P3))

All players begin with a score of 1200 at their first game.

Future improvements

There's a lot of them...

• Sort after completing
• Provide different options
• Variable K constant: weight by date
• Hook up google sheets API for easy updates
• UI for different calculation types