Information Technology (IT) Enables Systematic Design. In pre-Internet societies word of mouth emerged naturally and evolved in ways that were difficult to control or model. The Internet allows this powerful social force to be precisely measured and controlled through proper engineering of the information systems that mediate online feedback communities. Such automated feedback mediators specify who can participate, what type of information is solicited
from participants, how it is aggregated, and what type of information is made available to them about other community members. Through the proper design of these mediators, mechanism designers can exercise precise control over a number of parameters that
are difficult or impossible to influence in brick-andmortar
settings. For example, feedback mediators can
replace detailed feedback histories with a wide variety
of summary statistics; they can apply filtering
algorithms to eliminate outlier or suspect ratings; they
can weight ratings according to some measure of the
rater’s trustworthiness, etc. Such degree of control
can impact the resulting social outcomes in nontrivial
ways (see §§5.2–5.4). Through the use of information
technology, what had traditionally fallen within
the realm of the social sciences is, to a large extent,
being transformed to an engineering design problem.
Understanding the full space of design possibilities
and the impacts of specific design choices on
the resulting social outcomes is an important research
challenge introduced by these new systems.