More than Two Categories (2 of 3)

Frequency 
Better 
45
(33.333) 
Worse 
25
(33.333) 
Same 
30
(33.333) 
Total 
100 
The chi square statistic is then computed using
the formula:
The
degrees of freedom are equal
to the the number of categories 1. For this example,
Since there are three categories, the degrees of freedom equal
3  1 = 2. From a
chi square table,
it can be determined that the
probability value
is 0.039. Therefore, the null hypothesis of one third better, one third
worse, one third the same can be rejected.