# Evaluation of Methodologies and Measures on the Usability of Social Robots: A Systematic Review
## 3 Results
### Evaluation Dimensions
#### 3.3.4 Categorization of Social Robot's Evaluation Measures
As mentioned, a social robot is a utilitarian product and a hedonic product partly, so it is defined as an important attribute of intention to use a hedonic product [45]. We categorized constituents into three concepts: (1) appearance of a robot, (2) personality of a robot, and (3) perceived emotional value of a robot (Tables 6-9). \begin{table}
\begin{tabular}{c c c c} \hline \hline
**Measures** & **Count** & **Ratio (\%)** & **Reference** \\ \hline Anthropomorphism: Lifelike/Humanlike/Natural & 4 & 11\% & [11; 22; 23; 61] \\ \hline Scary/Fright & 3 & 8\% & [8; 19; 24] \\ \hline Sad & 3 & 8\% & [13; 24; 25] \\ \hline Angry & 3 & 8\% & [13; 24; 25] \\ \hline Worried/Depressing & 2 & 6\% & [34; 37] \\ \hline Lively & 2 & 6\% & [37; 60] \\ \hline Organic & 1 & 3\% & [19] \\ \hline Strange & 1 & 3\% & [19] \\ \hline Dangerous & 1 & 3\% & [19] \\ \hline Upset & 1 & 3\% & [38] \\ \hline Amusing & 1 & 3\% & [37] \\ \hline Alive & 1 & 3\% & [27] \\ \hline Elegant (Rough) & 1 & 3\% & [57] \\ \hline Strong (Weak) & 1 & 3\% & [57] \\ \hline Tense & 1 & 3\% & [61] \\ \hline \hline \end{tabular}
\end{table} 
Table 7: Appearance of a robot. \begin{table}
\begin{tabular}{c c c c} \hline \hline
**Measures** & **Count** & **Ratio (\%)** & **Reference** \\ \hline Actively engaged & 7 & 19\% & [20; 28; 57; 58; 60; 61; 62] \\ \hline Nice/Kind/Good (Awful/Unkind/Bad) & 6 & 17\% & [11; 19; 28; 57; 61; 63] \\ \hline Confident (Insecure) & 4 & 11\% & [10; 17; 28; 57] \\ \hline At ease/Relaxed/Calm & 4 & 11\% & [20; 28; 34; 57] \\ \hline Sociable (Unsociable) & 3 & 8\% & [18; 23; 61] \\ \hline Aggressive/Offensive & 3 & 8\% & [13; 19; 37] \\ \hline Interactive & 3 & 8\% & [13; 19; 51] \\ \hline Companionship/As a co-worker (Bossy) & 3 & 8\% & [13; 23; 51] \\ \hline Perceived emotional stability/Insensitive (Sensitive) & 2 & 6\% & [22; 61] \\ \hline Independent (Dependent) & 2 & 6\% & [10; 16] \\ \hline Exciting (Lame) & 2 & 6\% & [57; 61] \\ \hline Sympathetic (Unsympathetic) & 2 & 6\% & [51; 60] \\ \hline Receptive & 1 & 3\% & [28] \\ \hline Conscious (Unconscious) & 1 & 3\% & [11] \\ \hline Perceived pet likeness & 1 & 3\% & [22] \\ \hline Extrovert (Introvert) & 1 & 3\% & [57] \\ \hline Rational (Emotional) & 1 & 3\% & [57] \\ \hline Familiarity & 1 & 3\% & [27] \\ \hline Sincere & 1 & 3\% & [51] \\ \hline Shy & 1 & 3\% & [13] \\ \hline \hline \end{tabular}
\end{table} 
Table 8: Personality of a robot. Trust. Trust is defined as \"the belief that the system performs with personal integrity and reliability\" in Almere model [48]. The studies related to relational agent indicate that trustworthy is the main dimension to evaluate the agent [55; 64]. After this research published, Almere model also used trust as one of its constructs [48]. Based on trust in a social robot as an agent, the user can accept a piece of advice from a robot [51]. Consequently, there can be constant interaction with a robot and build a solid foundation for a relationship between a user and a robot. In [52], there are two individuals that can define trust--a trustor and a trustee. The trustor is an individual who is exposed to risk. The trustee can represent the other one who can give trust to the trustor. In the relationship between a user and a social robot, a user who will need help can be a trustor and then a social robot will play an opposite role as a trustee. Based on these relationship dynamics, we divided measures of trust into two groups: (1) trustworthiness of a robot, (2) acceptance toward an advice from a robot. However, we only collected a few measures of trust from previous researches and those are in Table 10. \begin{table}
\begin{tabular}{c c c c} \hline \hline
**Measures** & **Count** & **Ratio (\%)** & **Reference** \\ \hline Trustworthy/Credible/Compliance & I1 & 31\% & [9;10;16;18;19;21;23;28;51;57;62] \\ \hline Intelligent (Unintelligent) & 3 & 8\% & [23;51;61] \\ \hline Virtuous (Sinful) & 1 & 3\% & [51] \\ \hline Unselfish (Selfish) & 1 & 3\% & [51] \\ \hline \hline \end{tabular}
\end{table} 
Table 10: Measures of trust.