## 4 Results and Discussion
### ANOVA Results  
In this subsection, the analysis of variance (ANOVA) is conducted to assess the statistical significance of factors, along with their percentage contributions. First, the results of ANOVA based on the F test are exhibited in Tables 3-6. The critical F values, using a 5% significance level (95% confidence level) from the Fisher table are, respectively, F0.05 (1, 11) = 4.84, F0.05 (1, 3) = 10.13 and F0.05 (1, 2) = 18.51 for the full factorial, Plackett-Burman and Taguchi methods. Factors with an F-ratio greater than these critical values are considered statistically significant denoted by (*). Further, the percentage contributions (P%) of factors from the three methods are also given. The ANOVA tables show also the adjusted R-squared measure. Figure 6: Main effects on routing overhead (RO) from FFM, PBM and TM. \begin{table}
\begin{tabular}{c c c c c c c c c c c c c} \hline \hline \multicolumn{10}{c}{**Full Factorial**} & \multicolumn{5}{c}{**Plackett–Burman**} & \multicolumn{5}{c}{**Taguchi**} \\ \hline  & **DoF** & **F** & **P\%** & **Sig/Insig** & **DoF** & **F** & **P\%** & **Sig/Insig** & **DoF** & **F** & **P\%** & **Sig/Insig** \\ \hline ND & 1 & 242.8* & 84.9\% & Significant & 1 & 93.0* & 83.0\% & Significant & 1 & 550.1* & 88.6\% & Significant \\ NC & 1 & 7.3* & 2.5\% & Significant & 1 & 6.8 & 6.1\% & Insignificant & 1 & 488.8* & 7.9\% & Significant \\ NDxNC & \(-\) & \(-\) & \(-\) & \(-\) & \(-\) & \(-\) & \(-\) & 1 & 7.1 & 1.1\% & Insignificant \\ BKH & 1 & 3.9 & 1.4\% & Insignificant & 1 & 0.8 & 0.7\% & Insignificant & 1 & 6.4 & 1.0\% & Insignificant \\ WMH & 1 & 20.9* & 7.3\% & Significant & 1 & 8.4 & 7.5\% & Insignificant & 1 & 6.8 & 1.1\% & Insignificant \\ Error & 11 & \(-\) & 3.8\% & \(-\) & 3 & \(-\) & 2.7\% & \(-\) & 2 & \(-\) & 0.3\% & \(-\) \\ Total & 15 & \(-\) & \(-\) & \(-\) & 7 & \(-\) & \(-\) & \(-\) & 7 & \(-\) & \(-\) & \(-\) \\ Adj.R\({}^{2}\) & 0.633 & & & 0.791 & & & 0.788 & & & & \\ \hline \hline \end{tabular}
\end{table} 
Table 6: ANOVA significance and percentage contribution of the factors on routing overhead. \begin{table}
\begin{tabular}{c c c c c c c c c c c c} \hline \hline \multicolumn{10}{c}{**Full Factorial**} & \multicolumn{5}{c}{**Plackett–Burman**} & \multicolumn{5}{c}{**Taguchi**} \\ \hline  & **DoF** & **F** & **P\%** & **Sig/Insig** & **DoF** & **F** & **P\%** & **Sig/Insig** & **DoF** & **F** & **P\%** & **Sig/Insig** \\ \hline ND & 1 & 5.6* & 13.6\% & Significant & 1 & 19.2* & 21.7\% & Significant & 1 & 207.1* & 13.2\% & Significant \\ NC & 1 & 0.3 & 0.6\% & Insignificant & 1 & 8.7 & 9.8\% & Insignificant & 1 & 62.2* & 4.0\% & Significant \\ NDxNC & \(-\) & \(-\) & \(-\) & \(-\) & \(-\) & \(-\) & \(-\) & 1 & 10.4 & 0.7\% & Insignificant \\ WMH & 1 & 9.8* & 23.9\% & Significant & 1 & 25.0* & 28.2\% & Significant & 1 & 451.6* & 28.8\% & Significant \\ WMH & 1 & 14.6* & 35.6\% & Significant & 1 & 32.7* & 36.9\% & Significant & 1 & 836.2* & 53.3\% & Significant \\ Error & 11 & \(-\) & 26.9\% & \(-\) & 3 & \(-\) & 3.4\% & \(-\) & 2 & \(-\) & 0.1\% & – \\ Total & 15 & \(-\) & \(-\) & \(-\) & 7 & \(-\) & \(-\) & \(-\) & 7 & \(-\) & \(-\) & \(-\) \\ Adj.R\({}^{2}\) & 0.634 & & & & 0.821 & & & 0.981 & & & \\ \hline \hline \end{tabular}
\end{table} 
Table 4: ANOVA statistical significance and percentage contribution of the factors on PLR.