The coefficient of determination (R2) value of 0.975 for COD
removal, 0.986 for TN removal and 0.989 for power density showed
high significant regression for both the responses and justifies the
prediction adequacy of these three models. The coefficient of variation
(CV) measures the unexplained or residual variability in the
data as a percentage of the mean of response variable. The low
value of CV (6.07% for COD removal, 5.36% for TN removal and 2.41%
for power density) indicated good precision and reliability of the
experiments.