THE AVERAGE DOES NOT EXIST

The statisticians used to tell these jokes.
1. We humans have 1.999... legs on the average. It will happen when we take into account physically challenged people.
2. We have only one testicle. Again this will result when all women are taken into account.
3. In a survey, men were asked how many girl friends they have. Most of them reported one. But a few reported 5 to 10. Some even 100. If we take a simple average, the answer will be shocking and misleading.
We have to use not only average -mean, but also mode and median at the appropriate places. Let us explore.

MEAN: The average we use every day. It is got by adding all the items and dividing by no. of items. It is suitable for the data which cluster around a central value. Example: Height of male or female graduate students. Blood pressure values of persons in the age range 60-70.

MEDIAN: It is the number that lies in the middle when all the numbers in the data sheet are lined up in ascending order.Say, there are 51 students in a class. Marks are awarded for 100 in a particular subject. If the median of the marks is 75, it means that 25 students had scored above 75 and another 25 students scored below 75. It indicates a good performance. If the median is 23, we understand that the students had done badly.

MODE: It is the most common (occurring) number in the data set. In the case of average of legs, or number of wives,It is better to take the mode. We will definitely get 2 legs and 1 wife as average.

Normal temperature of the body, heart beats, BP value, sugar reading and other medical parameters are mostly average values. Today, we specify average range also.
Teachers teach not for highly intelligent students or the slow learners. But they teach for average students (who is not present in the class).
A state draws out finance budget for average man; A limited meal is designed for average appetite. A plane seat will fit only average sized man and so on.
In the world of averages we have to somehow fit ourselves in.
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