of individuals), and sentiment analysis (reasoning
about overall/authorial positivity/negativity). A
direct comparison might elucidate whether the
moderate success of our affinity-based model
derives more from the positivity/negativity
framework or the relationship-level focus of affinity.
We note that, in order to provide a baseline
evaluation of our system, we hand-authored the
action affinity lexicon of the Triangle-COPA
actions. While hand-authoring is simple and fast to
complete, careful design decisions have been made
to guarantee that hand-authoring will never impede
the generalizability of the system: for future use of
the system, the simple, numerical, and intuitively
meaningful content of the action affinity lexicon is
well-suited for crowd-sourcing or automated
learning. Further, unlike many probabilistic
automated reasoning systems, our model does not
rely on being fed absolute prior probabilities, thus
avoiding the difficult task of obtaining non-arbitrary,
non-biased absolute prior probabilities. Also in order
to provide a baseline evaluation of our system, we
serialized all logical Triangle-COPA literals,
including nested literals and literals indicated to
occur in parallel. Future work may investigate
strategies for more true-to-intention interpretation of
complex literal notation.
We now consider questions that were not
correctly answered. In two problems (questions 35
and 37), the possible Triangle-COPA answers are of
similar affinity, but only the correct answer is
consistent with certain nonsocial knowledge. For
example:
Question 35. A circle and a small triangle are
running alongside of each other. The circle slows
down and then stops. Why? (Correct: The circle is
exhausted from running. Incorrect: The circle is
sleepy.)
Human solvers access nonsocial commonsense
knowledge: for example, the knowledge that one
may be exhausted after one exerts oneself. Our
affinity-based model cannot capture this nonsocial
commonsense knowledge and, appropriately, leaves
these questions unanswered.
Two unanswered problems (questions 72 and 89)
depict the transitivity of affinity. For example:
Question 72. A big triangle and little triangle
are strolling together. A circle runs towards
them, picks up the little triangle and runs away.
How does the big triangle feel? (Correct: The big
triangle is upset. Incorrect: The big triangle is
happy.)
Our model correctly interprets that the Big
Triangle’s feelings (expressed in the possible
answers) are implicitly directed at the Circle. Yet,
the model believes the Big Triangle and the Circle
have not had any meaningful interactions and finds
the affinity relation between the Big Triangle and
the Circle to be uninformed. Consequently, our
model considers the Big Triangle’s negative feelings
(in the first answer) and the Big Triangle’s positive
feelings (in the second answer) to be equally
probable, and the question is left unanswered. We
note that our model readily perceives that the
affinity between the Big Triangle and Little Triangle
is pleasant and that the affinity between the Circle
and the Little Triangle is unpleasant; but, unlike
humans, our model does not conclude that the
affinity between the Big Triangle and the Circle is
therefore also unpleasant. This performance suggests
that in order to foster more human-like interpretation
our model should incorporate reasoning about the
transitivity of affinity. Social Balance Theory
mathematically characterizes the transitivity of
affinity in human social networks, and is well suited
to be incorporated into our system in future work
(Heider, 1946; Cartwright and Harary, 1956).
In one incorrectly answered problem (question
36) and seven unanswered problems (questions 2,
26, 40, 41, 54, 57, and 98), the Triangle-COPA
possible answers reflected similar underlying
affinity relations but differing underlying dominance
relations. For example:
Question 2. The triangle saw the circle and
started shaking. Why did the triangle start
shaking? (Correct: The triangle is scared. Incorrect:
The triangle is upset.)
Both answers are consistent with the negative
affinity relation between the Triangle and the Circle;
but only fear (the correct answer) is also consistent
with the Triangle’s submissiveness and the Circle’s
dominance in the Triangle-Circle relationship. The
significant number of questions requiring
interpretation regarding dominance suggests future
work should broaden the relationship model to
include the existing (undirected) affinity relation and
a novel directed dominance relation.
In order to more formally characterize the
deficiency in our model, we consider emotional
dimensions our model cannot currently capture. We
consider the three emotional dimensions proposed
by the Pleasure Arousal and Dominance (PAD)
emotional state model, which is often used for
emotion modeling and emotion measurement
(Mehrabian, 1996). In our current model, the PAD
dimension Pleasure, is captured by the skew of the