1) DATA PROVIDER
The major concern of a data provider is whether he can
control the sensitivity of the data he provides to others. On one
hand, the provider should be able to make his very private
data, namely the data containing information that he does not
want anyone else to know, inaccessible to the data collector.
On the other hand, if the provider has to provide some data to
the data collector, he wants to hide his sensitive information
as much as possible and get enough compensations for the
possible loss in privacy.