Mathematics · essential
Mean deviation about a value for frequency distribution for JEE
Calculation of standard deviation, variance and mean deviation for grouped and ungrouped data
Formula
\(\text{MD about }a=\frac{1}{N}\sum f_i|x_i-a|\)
Variables: \(x_i\): values or class marks, \(f_i\): frequencies, \(N=\sum f_i\), \(a\): chosen central value.
Conditions: For grouped data use class marks.
Mean deviation from mean/median for frequency tables.