# Robotic Motion Learning Framework to Promote Social Engagement
## 4 Discussion  
The aim of this research was to determine whether human-robot interaction could be improved by including imitation into the robot's behavior. The hypothesis for this study was that incorporating the use of an imitated move during OP2's emotion game will cause a change in the participant's emotional state towards the robot. The dependent variables which measured this hypothesis were participant posture, facial emotional state, incidence of mood contagion, and participant perception of robot autonomy. We examined whether these four approaches individually supported or did not support the hypothesis. The posture analysis category did not support the hypothesis, as the results of both the experimental and control groups were statistically insignificant. There was no obvious difference in behavior in terms of participant posture whether the robot imitated them or not. All experimental participants displayed positive facial emotional states towards new emotion primitives at a constant or increased rate after imitation. A total of 40% of control participants displayed  
Figure 9: Highlights from the user-survey, overall group impressions. Questions focused on robot believability, before and after completion of the emotion guessing game and imitation sequences. \begin{table}
\begin{tabular}{c c c c c} \hline
**Question** & **Mean Control Group Rating** & **Mean Experimental Group Rating** & \(t\)**-Value** & \(p\)**-Value** \\ \hline
3.3 & 3.6 & 4 & \(-1.208\) & 0.1275 \\
4.4 & 3.4 & 4.14 & \(-2.797\) & 0.0094 \\
4.6 & 3 & 3.86 & \(-1.767\) & 0.0538 \\ \hline \end{tabular} Note: Ratings have been converted from Likert scale wording to a corresponding numerical system. “Strongly Disagree” corresponds with a 1, “Disagree” with a 2, and so forth. The highest possible numerical score is a 5. N value for control group = 5. N value for experimental group = 7.  
\end{table} 
Table 8: Comparison of statistical significance of autonomy-focused survey questions. a diminished positive emotion rate after the same time checkpoint. Participants smiled more when interacting with OP2 after the robot imitated them. From this, we can infer the experimental group participants shifted to a more positive emotional state and became more engaged with OP2 after imitation. For these reasons, this category supports the hypothesis. More experimental group participants exhibited mood contagion than control participants. While the control participants only imitated two high arousal emotions (anger and surprise), experimental participants mimicked a wider spectrum of 6 emotions and an imitation move. The large majority of control participants' (80%) perception of the robot's autonomy decreased. Over 70% experimental participants' perception stayed constant or improved. We can infer that incorporating imitation improved the experimental participants' perception of the robot as a viable social agent while it interacted with them. These results support the hypothesis. Three of the four approaches used supported the hypothesis that [PERSON] performing imitation affects the emotional state of the participant towards the robot. This study shows that, while robotic imitation may not cause the participants to sit in a more open posture, the imitation does encourage the participants to assume a more positive emotional state, to develop a stronger sense of empathy for the robot, and to increase their perception of the robot as an independent social agent. As an interesting side note, there appeared to be an increased rate of responsive verbalization in experimental participants compared to their control group counterparts. All participants that started out by verbally responding to the robot's introductory greeting (\"Hi I'm [PERSON]!\") later replied goodbye to it at the end of the session. Experimental participants who did not greet the robot initially were more likely to reply goodbye to it at the end, compared to control participants who did not initially greet the robot.