Standard deviation
In: 4
Imagine you are a professor, standing in front of a large lecture hall partially filled with students.
Each student is a different distance away from you.
The *average* distance away from you is simply the total distance between you and each student added together and divided by the number of students.
But the average distance doesn’t tell you much about the spread of students in the room. For example, if there were 4 students, the average distance would be the same if those students were each sitting in one corner of the room or each sitting next to each other in the centre of the room.
The *standard deviation* tells you the average distance of each student *from the average distance between you and the students*. If that number is small, the students are close to each other, like the 4 students in the centre of the room. If it is large, they are far apart, like the 4 students in the corner.
Latest Answers