Expected Value

The expected value is one of the most fundamental measures for summarizing the average behavior of a random variable. Regardless of what happens in a single trial, it tells us what value the system tends toward over many repetitions. It plays a central role in financial risk, decision theory, reinforcement learning, and statistical modeling. Expected value is not just about computing an average; it is a way of summarizing uncertain outcomes within a single decision framework. That is why it is widely used in AI for reward, cost, and risk evaluation.