  When additional information sources are available, an important question for
an agent solving a certain problem is how to optimally use the information the
sources are capable of providing. A framework that relates information accuracy
on the source side to information relevance on the problem side is proposed. An
optimal information acquisition problem is formulated as that of question
selection to maximize the loss reduction for the problem solved by the agent. A
duality relationship between pseudoenergy (accuracy related) quantities on the
source side and loss (relevance related) quantities on the problem side is
observed.
