Social Interactions in Post-design Phases in Product Development and Consumption: Computational Social Science Modeling - Principia Designae: Pre-Design, Design, and Post-Design - page 148

avoid disconnections. This was essential to maintain the distinction between
'social' and 'non-social' runs in paired experiments.
The targets of social actions and influences interactions are always defined by
the perceptual categories mentioned earlier. In these experiments, Consumers are
only influenced by a single neighbor at a time. They do not poll their local social
network or perform any reasoning based on the range of values of other agents.
The utility function is a weighted sum of the three dimensions described above.
However, the weights are adaptive and have a degree of random 'jitter' to simulate
trial-and-error exploration of alternative utility functions. As mentioned previously,
utility is only realized after a Product is consumed, but this result feeds back into
Sensation, Perception, and Valuation via expectations.
In contrast, the valuation function operates on perceptions relative to an 'ideal
product' vector. The closer the Product is to the consumers ideal the higher the
valuation. It is measured as Euclidean distance between the sensed product and the
ideal, both of which are filtered by Sensation. Also, there is an adaptive filter for
valuation to model agent focus and prioritization, and also generalization.
In summary, at the task level the Consumer's problem is to find relatively more
desirable Products to consume by searching the Consumption Space and adjusting
their ideal product type. If they become dissatisfied during this process or if they are
not able to find products to consume, they interact socially to either modify their
value system or to move toward another agent in the Consumption Space.
At a social level, Consumers create and maintain social relationships through
physical contact in the Consumption Space. However, if a Consumer is close to
losing social connections, that Consumer interacts socially to build new connec-
tions through a referral process ('friends of friends'). The focus of social interaction
is on soliciting or offering information about another Consumers' ideal product. We
simulate the phenomena of opinion leadership and also susceptibility to influence
from others.
11.4.3 Producers
In the current implementation, Producer agents have a simple architecture focused
on two decision processes. They use simple decision rules based on local optimi-
zation and, unlike Consumers, do not have any other cognitive capabilities for
sensation, perception, conception, or affect. The only decisions they make are
(1) current production—choosing a replacement product from existing designs to
replenish inventory in response to Consumer acts of consumption, and (2) new
product introduction—choosing a new product designs to introduce from the
designs that are in the 'adjacent possible'. To decide on current production, the
Producer uses consumption statistics by region, and then makes their choice from
existing designs based on weighted random choice. Weights are set to be propor-
tional to consumption history in that region. Also, a fixed weight is given to recently