64-67, References from Master's Project Report

References from my Master's Project Report that I keep forgetting to Blog!...

64, A simple procedure for finding equitable allocations of indivisible goods, by Dorothea Herreiner & Clemens Puppe, 2000.

65, Issues in Multiagent Resource Allocation, by Yann Chevaleyre et al, 2006.

66, The Contract Net Protocol: High-Level Communication and Control in a Distributed Problem Solver, by Reid G. Smith, 1980.

67, A task-swap negotiation protocol based on the contract net paradigm, by Matteo Golfarelli, Dario Maio & Stefano Rizzi, 1997.

Deadlock in Implementation

After quite a few days debugging finally spotted the problem...

Consider the following case:

1) a1 initiates a proposal with a3 and a4.
2) a2 initiates the same proposal with a3 and a4.
3) a3 responds to a1 with acceptance.
4) a4 responds to a2 with acceptance.

In this situation a3 cannot respond to a2 and a4 cannot respond to a1. Both are stuck.

Now need to think what to do about it!

Assumptions as contraries of assumptions

I wanted the desirable property of not allowing two conflicting assumptions to hold simultaneously and thus added conflicting assumptions to the set of contraries for each assumption, e.g. asmHas(X,R) is set as a contrary of asmNotHas(X,R) and vice versa.

This introduces a couple of problems though:
(1) The defences of arguments get really large since there are now so many more attacks to consider/counter.
(2) Incorrectness! e.g. the contrary of asmHas(a2,r5) is notHas(a2,r5) supported by asmNotHas(a2,r5), but asmHas(a2,r5) counter-attacks asmNotHas(a2,r5) so the initial attack doesn't hold (wrongly).

I have commented out for now (in the implementation) assumptions as contraries of assumptions.