The Anderson-Darling test is defined as:
H0: The data follow a specified distribution.
Ha: The data do not follow the specified distribution
Test Statistic: The Anderson-Darling test statistic is defined as
A2=−N−S
where
S=∑i=1N(2i−1)N[lnF(Yi)+ln(1−F(YN+1−i))]
F is the cumulative distribution function of the specified distribution. Note that the Yi are the ordered data.