# Evaluation of Methodologies and Measures on the Usability of Social Robots: A Systematic Review
## 3 Results
### Evaluation Dimensions
#### 3.3.3. Most Frequently Used Measures from Recent Studies
\begin{table}
\begin{tabular}{c c} \hline \hline
**Evaluation Tool** & **Main Measures** \\ \hline SASSI(Subjective Assessment of Speech System Interfaces) [2] & system response accuracy, likeability, cognitive demand, annoyance, habitability, speed \\ \hline AttrakDiff/AttrakDiff 2 [3] & pragmatic quality, hedonic quality identification, hedonic quality stimulation, attraction \\ \hline NARS(Negative Attitude toward Robots Scale) [4] & negative attitude toward situations of interaction with robots, negative attitude toward social influence of robots, negative attitude toward emotions in interaction with robots \\ \hline Godspeedscale [5] & anthropomorphism, animacy, likeability, perceived intelligence, perceived safety \\ \hline RoSAS(Robot Social Attributes Scale) [19] & competence, warmth, discomfort \\ \hline \hline \end{tabular}
\end{table} 
Table 3: Evaluation tools and main measures. beliefs, social normative beliefs and control beliefs. Ease of use is was a subordinate concept of attitudinal beliefs. In [52], attitudinal beliefs included both utilitarian and hedonic product aspects. It referred to UTAUT and defined ease of use as a subordinate concept of the utilitarian aspect [55]. When they evaluated its voice interaction between a robot and a user, they use ease of use as one of the metrics. Ref. [9] referred to Almere model to evaluate the human-robot interaction, and Almere model contains ease of use as a measurement of user acceptance. Ref. [28] evaluated a social robot receptionist who can speak. As [52] did, ref. [28] used ease of use to measure users' satisfaction of its interaction between a social robot receptionist and a user. Trust. Refs. [9; 16; 18; 23; 28; 51; 52] In [52], they defined a concept of trust: \"a belief, held by the trustor, that the trustee will act in a manner that mitigates the trustor's risk in a situation in which the trustor has put its outcomes at risk\". In [18], they suggested a concept that a social robot as a viable solution to the psychometric assessment of the elderly. They referred to revised UTAUT to evaluate elderly participants' intention to accept and use this social robot. Ref. [48] defined trust as the belief in the system that the system performs the task with personal integrity and reliability. They divided the concept of trust into two items, the trust which a user has in the robot and to what extent the user intends to comply with the contents given by robots and on the nature of its interaction. In [53], trust was more important particularly in a high-risk situation and it directly affects the intention to use or acceptance of robot-decided information. Ref. [23] also pointed out that trust was an important factor to accept and use of social robots because the robot will actively take part in the decision making process. Ref. [23] used the trustworthiness scale that had 6 sub-measures of trustworthiness; honest, trustworthy, honorable, moral, ethical, genuine. Ref. [52] set two hypotheses: (1) Humor will increase trust. (2) Empathy will increase trust. To verify these, ref. [55] evaluated social robots in terms of three-way of appeal; robot appearance appeal, task appeal and content appeal. Trustworthiness was one of four measures to evaluate content appeal. It evaluated not only contents' hedonic value but pragmatic value. However, there was no significant relationship between humor-trust and also in empathy-trust in contrast with several previous research. Ref. [9] was referred to the Almere model to evaluate human-robot interaction scenario. They used trust as a measure of user acceptance. In [28], they designed exactly the same experiment with [52] to evaluate a social robot receptionist. They used trust to evaluate robot's contents. Ref. [16] considered trust as one of the important affective elements in human interaction with technology-based things. Trust was evaluated using empathy and physical touch as the measuring variables. Ref. [51] mentioned that trust is important when people accept others' recommendations.