Suppose a seller wants to sell a
finite collection of goods which can be
available in limited or unlimited supply. We have a set of potential
customers
and each customer specifies a single subset of goods she is interested
in and
the maximum price she is willing to pay for that subset. If the goods
are the
edges of a graph and customers are requesting to purchase paths in this
graph, then we can think of the problem as pricing computer network
connections or transportation links. We call such customers
single-minded as
they are interested in whole single subset of goods. The problem is to
compute the prices for goods so as to maximize the overall revenue of
the
seller.
In another setting we will consider, called unit-demand, each customer
also
declares a single subset of goods together with non-zero budgets for
each
single good, and a ranking of all the goods the customer is interested
in.
Once prices are fixed, each customer chooses to buy one of the goods
she
can afford based on some predefined selection rule, such as min-buying,
max-buying, and rank-buying. Again, the objective is to find the prices
of
goods to maximize the revenue of the seller.
In this talk we will consider the approximability of such problems, and
will
discuss both approximation algorithms and non-approximability results
for
some variants of these problems.
Parts of this talk will refer to joint work with Patrick Briest and
Martin Hoefer.