## 4 Result Analysis
### Efficiency  
In order to measure the efficiency, time taken by each team was recorded. The recorded data shows that the time taken by team T2 was more than the time taken by team T1. The boxplot is used to express the results to show the time comparison between team T1 and team T2.  
Figure 12 shows the boxplot for team T1 and team T2. The boxplot for team T1 has a median of 89 min. The whiskers show that minimum time taken by a member of team T1 to identify a requirement was 50 min and the maximum time taken by a member a member of T1 was 120 min. For team T2, boxplot shows that maximum time taken by a member of team T2 was 180 min and minimum time taken by a member of team T2 was 70 min. The median time taken by members of team T2 was 120 min.  
The time taken by team T2 was more because members of team T2 waited for the response from users whom they sent a request to do a survey. Also, requirements engineers of team T2 conducted interviews to elicit requirements which also took more time, while the team T1 used the SNS-based approach to conduct RE activities and they found a huge population on SNS at once and did not take more time to elicit user requirements. Therefore, the results demonstrate that the SNS-based proposed RE approach takes less time to conduct overall activities.  
Figure 13 shows the boxplot in order to compare the time taken by both teams to identify VR and CR. The median time for team T2 was 38 min for each participant to determine VR and CR. The whiskers show that minimum time taken by a participant of team T2 was 36 min and maximum time taken by participants of team T2 was 80 min to identify VR and CR. This was due to the fact that  
Figure 12: Boxplot for total time taken by two teams to execute the RE task.  
\begin{table}
\begin{tabular}{c c c c c|c c c c} \hline \hline  & \multicolumn{3}{c|}{**T1**} & \multicolumn{3}{c}{**T2**} \\ \hline  & **FR** & **NFR** & **CR** & **VR** & **FR** & **NFR** & **CR** & **VR** \\ \hline
**App** & 101 & 27 & 91 & 32 & 39 & 4 & 37 & 11 \\
**Design** & 74 & 25 & 76 & 28 & 24 & 7 & 22 & 4 \\
**Total** & 175 & 52 & 167 & 60 & 63 & 11 & 59 & 15 \\ \hline \hline \end{tabular}
\end{table}
Table 8: Comparison of Team “T1” and Team “T2” over Requirements.  
there were more conflicts among participants as to whether the requirements should be categorized as common or variable requirements. The domain experts were frequently involved to help to resolve the conflicts.  
The boxplot also shows that participants of team T1 took less time to identify variable and common requirements. The participants in team T1 took 27 min median time.  
The maximum time taken was 40 min and the minimum time taken was 10 min to determine VR and CR. The median time was a little closer to the mean time of team T2 because the requirements engineers found some keywords which were different but were either synonyms or variations of an already existed keyword. Therefore, the requirements engineers had to decide about the VR and CR of requirement in this case. The overall time taken by team T1 was less because they determined VR and CR of requirements based on the predefined equation (Equation (1)).