Statistical deviation

According to the statistical deviation, any relatively usual behaviour or characteristic can be thought of as normal and any behaviour that is different to this is abnormal. For example, we can say that only a small number of people have an irrational fear of buttons, and so this fear is abnormal.

The statistical approach is best when dealing with characteristics that can be reliably measured, for example, intelligence. The average IQ is set at 100 and 68% of people have an IQ between 85 and 115. Only 2% of people have a score below 70, and these…