Commitment models and concurrent bilateral negotiation strategies in dynamic service markets

Technologies such as Web Services, the Semantic Web and the Grid may give rise to new electronic service markets, which have so many services, providers and consumers that software agents need to be employed to search and configure the services for their users. To this end, in this thesis, we investigate bilateral negotiations between agents of service providers and consumers in such markets. Our main interest is in decommitment policies or rules that govern reneging on a commitment, which are essential for operating effectively in such dynamic settings.The work is divided into two main parts. In part I (chapters 3-8), we investigate how the decommitment policies, through the parties’ behaviour, affect the combined utility of all market participants. As a tool, we use decisions that parties make during their interaction. These decisions have previously been discussed in the law and economics literature, but this is the first empirical investigation of them in a dynamic service market setting. We also consider settings (for example, with incomplete information) that have not been addressed before. In particular, we take four of these decisions — performance, reliance, contract and selection — and consider them one by one in a variety of settings. We create a number of novel decommitment policies and increase the understanding of these decisions in electronic markets.In part II (chapters 9-11), we consider a buyer agent that engages in multiple negotiations with different seller agents concurrently and consider how decommitment policies should affect its behaviour. Specifically, we develop a detailed adaptive model for concurrent bilateral negotiation by extending the existing work in several directions. In particular, we pay special attention to choosing the opponents to negotiate with and choosing the number of negotiations to have concurrently, but we also address questions such as bilateral negotiation tactics and interconnected negotiations on different services. These ideas are again evaluated empirically