What is the Kelly Criterion and what is this website all about?

This website is a tool to be used for Starcraft 2 Fantasy league or sports betting purposes. It takes a set of "odds" for a matchup between two Starcraft players, queries API for Aligulac, the most used Starcraft 2 progamer player rating database, retrieves the expected win rate for player A in the matchup, and uses the Kelly Criterion formula to determine the optimal % of your bankroll to be bet on player A (a negative Kelly value indicates you should skip the opportunity). The ratings provided by Aligulac are just estimations, so this is a tool only to compliment your normal decision making process.

The Kelly Criterion is a mathematical formula used in multi-stage investing and sportsbetting situations which determines the optimal percentage of your "bankroll" to wager on a particular opportunity. When a +EV (expected value) opportunity is available to you, it's clear that you should risk SOME of your bankroll on the opportunity, but it's not obvious what the optimal percentage of the bankroll to be used is. The Kelly Criterion takes in the expected return rate and a rate of success projection, and returns the Kelly Value, the percentage of your bankroll which you should risk.