3.1.1.4. Social and situation awareness

An important aspect of day-to-day interaction is the ability to perceive and abstract information from the environment. This phenomenon is termed as situation awareness and it helps in decision making, planning and responding accordingly while interaction. By use of various sensors a robot can be designed to sense its surroundings or perceive emotional condition of its interacting partner. Based on this information it can create a goal oriented understanding of its environment and finally respond either based on past experience, mimicry or adaptation. Nevertheless it is not surprising that human robot interactions might fail when at times even human-human interactions do. Giuliani et al. [38], described two types of failures in HRI, i.e. social norm violations and technical failures. Any deviation from the social script or the usage of the wrong social signals (i.e. correct action execution but inappropriate for the given situation) due to incorrect judgment of the robot is usually considered as social norm violation. On the other hand if a robot judges the situation correctly and selects the appropriate action but the action is poorly executed then this is termed as technical failure.

3.1.2. Assessment and evaluation methodologies

Includes psychometric measures, questionnaires, and/ or surveys for personal assessment of participants in response to the robot and

Includes observation of human participants behavior while interacting with the agent.

Observation of user behavior towards the agent repeatedly over a period of time.

Involves more than one person or one robot; pre-set variables in the selection criteria for task

performance.

Table 1. Existing evaluation methodologies for HRI.

interaction.

Evaluation methodologies

Behavioral measurements

Psychophysiological measures

Task performance metrics

Selfassessments and subjective evaluation

As social HRI is gaining attention of the research community, a growing need is occurring for strong and efficient methods of its assessment and evaluation. Currently most of the assessment and evaluation criterion used in HRI are adapted from HCI either per se or with slight modifications. According to Beer et al. [36], assessment methodologies for HRI can be commonly characterized as process-oriented, diagnostic approach, ongoing and continuous. Similarly the evaluation methodologies include product-oriented, judgmental approach, final and discrete evaluations. Once again the factors that model HRI also decide which assessing methodologies are most suitable for it. Assessments can however be carried out in combination as well. Beer et al. [36] grouped existing assessment methodologies into three basic groups i.e. Social models which mainly involve assessment of emulation of empathy during HRI; technology acceptance model (TAM) and similar methodologies which represent user acceptance; behavioral adaptation model. Both the assessment and evaluation methodologies can be objective (e.g. task success, dialog quality and dialog efficiency etc.) or subjective (UTAUT model, Godspeed questionnaire etc.). Existing evaluation methodologies on HRI can also be divided as primary and non-primary based on how (i.e. directly or indirectly) they evaluate the HRI model. Popular primary evaluation methodologies used for human studies HRI include methods like self-assessments and subjective evaluations, behavioral measurements,

Description Strengths Weaknesses

quantified.

Easily implemented, easily

Can be implemented in combination with other methodologies, e.g. selfassessment and subjective evaluation and psychobehavioral measures.

Objective hence less biased; noninvasively measures stress and response of participants; video based reduces Hawthorne effect.

Good for team scoring; less biased; good for evaluating HRI involving humanoids; good for HRI involving non-verbal behaviors in addition to verbal

ones.

Possibility of inaccuracy due to mental state and interpretation capabilities of the human participant; oriented towards engineering and leaves out social interaction perspective.

Socially Believable Robots

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http://dx.doi.org/10.5772/intechopen.71375

Can lead to misinterpretations due to complexity; requires prior

participants; time consuming due to longitudinal in nature.

Not suitable for one-to-one HRI; less flexible method; not generalized enough for every HRI model; not suitable for robots other than humanoids or HRI which involves mainly verbal behaviors and not nonverbal cues; limited application

Can be biased due to "Hawthorne effect".

knowledge of human

areas.

### 3.1.1.5. Verbal and non-verbal communication

Interaction between two or more participants is usually termed as a dialog. Exchange of information is the prime objective of a dialog. When humans engage in a dialog, they usually rely on a variety of para-linguistic social cues (i.e. facial expressions and gestures, etc.) in addition to words. Research [39], has proven such non-verbal cues to be highly effective for controlling human robot dialog. However robot's inability to fully interpret speech signals (e.g. pitch and tone etc.) alone, for complete comprehension of human emotions during an interaction can cause interaction failure. Gestures, facial expression and body movements add extra clues for the robot to understand the mental state of the participant and respond accordingly.
