l Sturges rule How to set the approximate number of classes to begin constructing a frequency distribution k=1+3322(l0g10n) 10 where k= approximate number of classes to use and n= the number of observations in the data set o 2002 The Wadsworth GroupSturges’ rule • How to set the approximate number of classes to begin constructing a frequency distribution. where k = approximate number of classes to use and n = the number of observations in the data set . © 2002 The Wadsworth Group k =1+3322 n 1 0 . (log )