Absolute deviation

Absolute deviation is a way of measuring how spread out some numbers are. Imagine that your friend has just asked you to guess how tall different people in your class are. You might start by guessing the average, which is just the total of all the heights divided by how many people there are. However, your answer might not be close to the actual heights of everyone in your class. That's when absolute deviation comes in! Absolute deviation measures how far away each person's height is from the average. In other words, it tells you how much the heights are all spread out.