A martingale is a stochastic process that represents a fair game, where the expected value of the next observation is equal to the present observation, meaning there are no predictable trends in the outcome. In other words, given all past information, the future expected value remains constant, which highlights the concept of 'fairness' in gambling and various applications in probability theory and finance. This property makes martingales significant in analyzing various systems where uncertainty plays a key role.
congrats on reading the definition of Martingale. now let's actually learn it.