Maths Class 11 Chapter 15. Statistics | Page 4

All data is given equal importance in Mean , the extreme values are not ignored .
For Ungrouped data , Median :
Let ’ s arrange their score in ascending order in blue table . Now we will take the middle most score . Since we are talking about central tendency of data , middle most score should also reflect central tendency of data . Middle most score for May is 8 , while that of Hari is 10 . So based on middle score or median data , Hari has performed better .
When the number of observations ( n ) is odd , the median is the value of the (( n + 1 )/ 2 ) Th observation .
When the number of observations ( n ) is even , the median is the mean of ( n / 2 ) & ( n / 2 + 1 ) Th observations .
Median Ignores extreme values & Tells the point from where 50 % data is lesser and 50 % data is more