In this paper we suppose an agent that has a knowledge base written in
logic programming and sets of beliefs under the answer set semantics.
We then consider the following two problems:
given two logic programs P1 and P2, which have the sets of
answer sets AS(P1) and AS(P2), respectively;
(i) find a program Q which has the set of answer sets
such that AS(Q)=AS(P1) ∪ AS(P2);
(ii) find a program R which has the set of answer sets
such that AS(R)=AS(P1) ∩ AS(P2).
A program Q satisfying the condition (i) is called
generous coordination of P1 and P2; and
R satisfying (ii) is called rigorous coordination of P1 and P2.
Generous coordination retains all of the original belief sets of each agent,
but admits the introduction of additional belief sets of the other agent.
By contrast, rigorous coordination forces each agent to give up some
belief sets, but the result remains within the original belief sets
for each agent.
We provide methods for constructing these two types of coordination
and discuss their properties.
Keywords: answer set programming, coordination, program composition.