The Average

You hear the term "average" mentioned day in day out. The "average" guy. "Average rainfall on this date." A baseball players "average." A car gets an "average" of 35.3 miles per gallon.

The term "average" is a cultural rather than a statistical term. A tomato is technically a fruit but it's regarded culturally as a vegetable. David Stockman, head of something in the Reagan administration referred to ketchup as a vegetable.

Usually, the average is used as a measure of central tendency. Central tendency is the tendency of things to bunch together. Generally we mean by "average" the arithmetic mean, the total of all observations divided by the number of observations.

If Tiger Woods in a given golf round has 10 rounds of 4, 5 rounds of 3, and 3 rounds of 5, he has a total score of 70 and an average of 3.89 shots (rounding to the 100s place) per hole. How much does this tell you about how well Woods actually played that day? Not much, but it's one piece of data.

You have to be careful because what "average" you should use depends on the kind of information you have. An "average" man doesn't mean much because you can't really calculate an average. You can have average height or average weight but not an average man.

There's also different kinds of averages.

When you say, "He's just an average Joe," you usually mean "He's just a typical guy." That can get us into trouble.

For more on this go to Wikipedia or go to any statistics text book. Or you can look at some of my earlier blogs.

Entrepreneurship is the life's blood of all my professional activities. It makes them go. And go read my mystery for free at wwww.kearneymusicschoolmurders.blogspot.com or buy it from Amazon.com more cheaply than you can print it out.