# Nature-Inspired Optimization Algorithms for Text Document Clustering--A Comprehensive Analysis
## 5 Experiments Results and Discussion
### Results and Discussion
\begin{table}
\begin{tabular}{l c c c c c c c c c} \hline \hline
**Ranking** & \multicolumn{8}{c}{**Comparative Algorithms**} \\ \cline{2-10}
**Dataset** & **HS** & **GA** & **PSO** & **ACO** & **KHA** & **CS** & **GWO** & **BA** & **K-Mean** \\ \hline DS1 & 5 & 9 & 7 & 4 & 6 & 8 & 1 & 3 & 2 \\ DS2 & 4 & 7 & 2 & 3 & 8 & 5 & 1 & 6 & 9 \\ DS3 & 4 & 9 & 8 & 3 & 6 & 5 & 1 & 2 & 7 \\ DS4 & 8 & 9 & 6 & 2 & 7 & 4 & 1 & 3 & 5 \\ DS5 & 8 & 9 & 5 & 2 & 3 & 6 & 7 & 1 & 4 \\ DS6 & 7 & 9 & 5 & 2 & 6 & 8 & 1 & 3 & 4 \\ DS7 & 7 & 9 & 6 & 4 & 8 & 3 & 1 & 5 & 2 \\ \hline Summation & 43 & 61 & 39 & 20 & 44 & 39 & 13 & 23 & 33 \\ Mean rank & 6.14285 & 8.71428 & 5.57142 & 2.85714 & 6.28571 & 5.57142 & 1.85714 & 3.28571 & 4.71428 \\ Final ranking & 7 & 9 & 5 & 2 & 8 & 5 & 1 & 3 & 4 \\ \hline \hline \end{tabular}
\end{table} 
Table 6: The results of the [PERSON] ranking test for the comparative methods using the Precision values. Figure 3: The Precision results of the comparative methods using seven datasets. The results of the [PERSON] ranking test for the comparative methods (i.e., Harmony Search (HS) Algorithm, Genetic Algorithm (GA), Particle Swarm Optimization (PSO) Algorithm, Ant Colony Optimization (ACO), Krill Herd Algorithm (KHA), Cuckoo Search (CS) Algorithm, Gray Wolf Optimizer (GWO), Bat-inspired Algorithm (BA), and K-means technique.) using the Recall values are given in Table 8. In this Table, the rank of each results, summation, mean ranking, and final ranking results. The GWO got the first ranking, followed by ACO, it got the second ranking, BA got the third ranking, K-means got the fourth ranking, HS got the fifth ranking, CS got the fifth ranking, PSO got the seventh ranking, KHA got the eighth ranking, and finally, GA got the ninth ranking. Moreover the summation ranking for the given algorithms using the seventh datasets are given as HS got 38, GA, got 59, PSO got 41, ACO got 20, KHA got 42, CS got 38, GWO got 18, BA got 26, and K-mean got 33. These results can show the significant ability of the nature-inspired optimization algorithms to solve the text clustering problems. Moreover, the differences between the obtained results are slight and there is no much variation. In Table 9, the results of the comparative methods using seven datasets (i.e., Harmony Search (HS) Algorithm, Genetic Algorithm (GA), Particle Swarm Optimization (PSO) Algorithm, Ant Colony Optimization (ACO), Krill Herd Algorithm (KHA), Cuckoo Search (CS) Algorithm, Gray Wolf Optimizer (GWO), Bat-inspired Algorithm (BA), and K-means technique.) in terms of F-measure measure. It is clear that the basic nature-inspired algorithms that have been selected in this experiment have almost the same performance in solving the given text clustering problems. For example, the KHA got 0.507064 F-measure value in dataset number 1 and 0.418632 in dataset number 7. Also, for another example, the GWO got 0.637902 F-measure value in dataset number 1 and 0.527244 in dataset number 7. The results show differences in the outcomes according to the given values in Figure 5. It is obvious that the performance of the used nature-inspired optimization algorithm almost the same and GWO is better than almost all the given nature-inspired optimization algorithms. The results of the [PERSON] ranking test for the comparative methods (i.e., Harmony Search (HS) Algorithm, Genetic Algorithm (GA), Particle Swarm Optimization (PSO) Algorithm, Ant Colony Optimization (ACO), Krill Herd Algorithm (KHA), Cuckoo Search (CS) Algorithm, Gray Wolf Optimizer (GWO), Bat-inspired Algorithm (BA), and K-means technique.) using the F-measure values are given in Table 10. In this Table, the rank of each results, summation, mean ranking, and final ranking results. The GWO got the first ranking, followed by ACO, it got the second ranking, BA got the third ranking, K-means got the fourth ranking, PSO got the fifth ranking, CS got the sixth ranking, HS got the seventh ranking, KHA got the eighth ranking, and finally, GA got the ninth ranking.