Regression to the Mean – A Letter From 1987

Regression to the Mean by Anderson Griggs

I often hear from many of you that you know very little about investing.  However, I find that most of you understand investing quite well.  Many of the concepts and theories thrown out by those of us who claim to be professionals can be restated into words and phrases you use regularly.  For instance, when you say, “what goes up must come down,” or, when you are going through a particularly tough time, “don’t worry, things will get better,” you are showing your knowledge of regression to the mean.

We have a deep conviction that things will return to normal with time.  It is the driving force behind our security selection and...