Quoto

Learn / Library / Market making

Edge on a binary contract

Market makingMedium

A contract pays if an event happens and otherwise. The event has probability . A market maker sells units at . What is the total expected profit?

Checking an answer needs JavaScript. The hint and the solution open without it.

A whole number, a decimal, a fraction like 3/8 or a percent.

Hint

The fair value is probability times payout.

Solution
  1. The fair value is .
  2. The edge per unit sold is .
  3. The total expected profit on units is .

Answer: