2.9. Statistical evaluation
All the experiments were repeated for three different times, and
duplicate samples were analyzed at each sampling time. Data were
analyzed with the SPSS statistical package (ver. 15.0, Chicago). The
significant difference was defined as P < 0.05. One way analysis of
variance was used, and the significant differences were evaluated
by the Duncan multiple range test.
The compatibility of the rheological models with experimental
data was determined by using a non-linear regression analysis of
statistical software package SPSS (ver. 15, Chicago). The regression
coefficient (R2), root mean square error (RMSE) (4) and chi-square
(c2) (5) values were calculated. Duncan test was applied as a
comparative statistical analysis. The statistical criteria of having
highest R2, lowest RMSE and lowest c2 were chosen for selection of
best model for fitting.