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Chapter 6. Experimental Validations - Social Phobia
2.80 when considering only the subjects who looked at the character throughout the whole
exercise. This corresponds to a neither normal nor abnormal evaluation when considering all
subjects. However, it corresponds to a fairly normal evaluation when considering only the
subjects who looked at the character throughout the talking exercise.
From our results, we can see that the subjects have clearly identified the difference between
a bored and an attentive character. Not only are the scores to the bored and attentive
characters clearly categorized, but the SDs are also small, which indicates small variations
in scoring between the 12 subjects. These values are shown in parentheses in Table 6.11.
Moreover, from the responses we obtained for the 5th question, many subjects reacted very
negatively to the bored character. We received feedbacks such as “he could not care less
about what I was saying”, “I almost made her cry”, or “he was more than distracted, almost
condescending”. We also received feedbacks such as “she was making me think of a lover
who was drinking my words”, “he was very interested and receptive”, or “he was faking he
was interested” for the always attentive character. The results to the random version of the
scene were slightly above the mean value of 3 with SDs of 0.80 and 1.08 for the first and
second questions respectively. This seems quite logical since the characters for this scene
would alternatively be attentive or bored, and that we usually are more receptive to negative
attitudes than to positive ones. For some of the subjects, there were more positive attitudes
than negative ones and vice versa, which explains the higher SD values. For the tracked
version, the results we obtained were very similar to those of the random version. However,
when considering only the people who looked at the character throughout the whole talking
exercise, these values came closer to those of the attentive version, which equally seems logical.
Indeed, we hypothesized that such a closed loop induced by the subject’s gaze behavior
characterized an interaction through which the subject is empowered as he/she can perceive
he/she has an influence on the outcome of the interaction (note that the subjects were not
told about the potential influence of their gaze behavior). However for such a feedback to
be built, it is first necessary for the subject to make eye contact with the virtual character.
Hence, a lack of motivation from the subject prevents the triggering of such a positive feedback
loop. The SDs equally sustain this hypothesis since their values are quite high when
considering all subjects and decrease when considering only the subjects who looked at the
character during the exercises.
The lack of involvement from some subjects may explain the answers to the fourth question
concerning the normality of the characters. The bored version scored slightly under 4,
corresponding to fairly abnormal, which is what we expected to obtain. However, for the
attentive version, the score corresponds to a slightly normal evaluation. It is not surprising
to see a better scoring than for the bored version, but we did not expect it to be the best out
of the four. It seems as though the subjects were expecting the virtual character to be always
attentive to them. The characters from the random version appeared to be more normal to the
subjects than the characters from the bored version, which is what we expected. However,
they seemed less normal than characters from the attentive version, possibly for the reason
highlighted above (i.e. a bias from the subject towards an expectation of an always attentive
virtual character). For the tracked version, the same comments apply. However, it is important
to note that the characters seemed more normal to the subjects in the tracked version of
the scene than in the random one which is in line with our second hypothesis.
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