Returns explained
Decimal, fractional, American — three ways of writing the same thing. Here's how to read any price and the probability hiding inside it.
The three formats
Decimal (2.50) is the cleanest: your total return per unit staked, including your allocation. Fractional (3/2) shows profit relative to allocation. American (+150 / -200) uses a $100 reference — positive is profit on a $100 position, negative is the allocation needed to win $100.
They're interchangeable. Yoseri shows decimal by default because it makes edge and EV math obvious.
Implied probability
Every price contains a probability. For decimal returns, implied probability = 1 / returns. So 2.50 implies 40%, 1.50 implies 66.7%.
If you think the true chance is higher than the implied one, the position is +EV. If it's lower, the broker has the edge. This single comparison is the heart of value trading.
The vig, and how to remove it
Add up the implied probabilities of a market and you'll get more than 100% — the excess is the broker's margin. To estimate true probabilities you 'devig': normalise the implied probabilities back to 100%.
Comparing devigged prices across brokers reveals which one is offering the genuine value — the core of what Yoseri does automatically across 100+ brokers.
Why line shopping matters
Small price differences compound enormously. Consistently taking 1.95 instead of 1.90 on the same positions can be the difference between a losing and a winning year. Always take the best available number.
Theory is nice. Edges pay.
Yoseri does the pricing, edge and portfolio math for you — free to start, no card.