Five Point Summary : Box and Whisker Plots

One evening, when you were reading newspaper and your ten year old son came to you and announced that he scored 90 marks in Mathematics and scored 80 in English and rushed to play cricket. 
You were Happy and Sad at the same time. If 90 makes you Happy and 80 makes you sad, Think again!
Well, next day when visited his class, you received new information.
In Mathematics, everyone in the class got more than 90 marks and the class average is 95. In English, everyone is below your son. He is the topper! You are Happy and Sad again!
Well, that means more the information, more the clarity.
More information does not mean all marks of all the children in all the subjects. 
So, you need summary.  The best summary that can describe data is 5 Point Summary.
What are those five points? ( The simple definitions are  from wiki.paranormalcop.org)
   1.Minimum - the value above which there is 100% data
   2.First Quartile - the value above which there is 75% data
   3.Median (second quartile) - the value which divides the data set into two equal halves, 50% above and       50% below
  4.Third Quartile - the value above which there is 25% data
  5.Maximum - the value above which there is no data.
These five points can be represented in a graph that is called Box and Whiskers plot.

Before taking a look at the graphs and template ,here are the basics.
Watch these wonderful videos.


Creating Box plots in Excel is quite tricky as excel does not offer a straight forward chart type for the same.
Here is a Box and Whiskers Plot template created for you.
You can create up to 10 plots. 
Download the excel  from @Downloads .
This is a Do ..Co..Mo stuff  : Download, Copy and Modify at your will.
Few Ideas to get started.
1. Plot employee performance scores before and after training. You may be able to find out training impact!
2. Plot employees Incentive earnings of last 2 years… You may understand the truth of employee earning!

Here is a wonderful article named  Visual Presentation of Data by Means of Box Plots 
by D.L. Massart,a J. Smeyers-Verbeke,a X. Caprona and Karin Schlesierb

Here is another great resource for special excel charts.



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