Abstract
Task (re)allocation is a key problem in multiagent systems. Several different contract types have been introduced to be used for task reallocation: original, cluster, swap, and multiagent contracts. Instead of only using one of these contract types, they can be interleaved in a sequence of contract types. This is a powerful way of constructing algorithms that find the best solution reachable in a bounded amount of time. The experiments in this paper study how to best sequence the different contract types.
We show that the number of contracts performed using any one contract type does not necessarily decrease over time as one might expect. The reason is that contracts often play the role of enabling further contracts. The results also show that it is clearly profitable for the agents to mix contract types in the sequence. Sequences of different contract types reach a solution significantly closer to the global optimum and in a shorter amount of time than sequences with only one contract type. However, the best sequences consist only of two interleaved contract types: original and cluster contracts. This allows us to provide a clear prescription about protocols for anytime task reallocation.
Supported by NSF CAREER award IRI-9703122 and NSF grant IRI-9610122.
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Andersson, M.R., Sandholm, T.W. (1999). Sequencing of Contract Types for Anytime Task Reallocation. In: Noriega, P., Sierra, C. (eds) Agent Mediated Electronic Commerce. AMET 1998. Lecture Notes in Computer Science(), vol 1571. Springer, Berlin, Heidelberg. https://doi.org/10.1007/3-540-48835-9_4
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DOI: https://doi.org/10.1007/3-540-48835-9_4
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