(Alle Abstracts einblenden)
(Alle Abstracts ausblenden)
2009
-
Jens Witkowski.
Eliciting Honest Reputation Feedback in a Markov Setting.
In
Proceedings of the 21th International Joint Conference
on Artificial Intelligence (IJCAI 2009).
2009.
(Abstract einblenden)
(Abstract ausblenden)
(PDF)
Recently, online reputation mechanisms have been proposed that
reward agents for honest feedback about products and services
with fixed quality. Many real-world settings, however, are
inherently dynamic. As an example, consider a web service that
wishes to publish the expected download speed of a file
mirrored on different server sites. In contrast to the models
of Miller, Resnick and Zeckhauser and of Jurca and Faltings,
the quality of the service (e.g., a server's available
bandwidth) changes over time and future agents are solely
interested in the present quality levels. We show that
hidden Markov models (HMM) provide natural generalizations of
these static models and design a payment scheme that elicits
honest reports from the agents after they have experienced the
quality of the service.
-
Jens Witkowski.
Truthful Feedback for Reputation Mechanisms.
Diplomarbeit,
Albert-Ludwigs-Universität,
Freiburg, Germany 2009.
(Abstract einblenden)
(Abstract ausblenden)
(PDF)
Reputation mechanisms such as those employed by Amazon and
eBay offer an effective way to prevent market failure in
online economies. However, most of these mechanisms assume
that the privately monitored transaction outcomes are honestly
reported. This clearly is a simplification since buyers may
have incentives to misreport. While it has been shown that the
truthful elicitation of these outcomes is feasible in settings
with pure adverse selection, i.e. with a purely
stochastic seller, we study whether honest feedback can
be elicited in settings with moral hazard, i.e. with a
strategic seller. For a pure moral hazard setting
motivated by the one at eBay, we find that there is no
feedback mechanism that makes honest reporting a best response
to truthful play by all other players. For a combined setting
with both adverse selection and moral hazard, however, we
retrieve a positive result and construct a payment scheme that
can be used as a "feedback plug-in" for reputation mechanisms.
2008
-
Jens Witkowski.
Eliciting honest reputation feedback in a Markov setting.
Studienarbeit,
Albert-Ludwigs-Universität,
Freiburg, Germany 2008.
(PDF)
