Locally constrained homomorphisms on graphs of bounded treewidth and bounded degree.

A homomorphism from a graph G to a graph H is locally bijective, surjective, or injective if its restriction to the neighborhood of every vertex of G is bijective, surjective, or injective, respectively. We prove that the problems of testing whether a given graph G allows a homomorphism to a given graph H that is locally bijective, surjective, or injective, respectively, are NP-complete, even when G has pathwidth at most 5, 4 or 2, respectively, or when both G and H have maximum degree 3. We complement these hardness results by showing that the three problems are polynomial-time solvable if G has bounded treewidth and in addition G or H has bounded maximum degree

Managing Online Auctions: Current Business and Research Issues

The Internet's computational power and flexibility have made auctions a widespread and integral part of both consumer and business markets. Though online auctions are a multi-billion dollar annual activity, with a growing variety of sophisticated trading mechanisms, scientific research on them is at an early stage. This paper analyzes the current state of management science research on online auctions. It develops a broad research agenda for issues such as the behavior of online auction participants, the optimal design of online auctions, the integration of auctions into the ongoing operation of firms, and the use of the data generated by online auctions to inform future trading mechanisms. These research areas will draw from applied and theoretical work spanning management science, economics, and information systems.Auctions, Internet

Designing sniping agents

10.1007/s10479-008-0366-6Annals of Operations Research1681291-30

A mechanism for supporting collective innovation: the open contract-based challenge

The paper proposes a multi-attribute combinatorial auction-based mechanism, called open contract mechanism (OCM), which allows an organization or an individual (seeker) to dynamically and simultaneously bargain the features of distinct innovation contracts with other organizations and individuals (solvers), in general collective innovation environments. In such contexts, a seeker does not possess specific skills and technical knowledge which are crucial for an innovation or for a part of a new product development project, while some solvers might be willing to provide their relevant know-how to the seeker. To induce collaboration between the seeker and solvers, voluntary and legally enforceable agreements need to be formulated, where a fair evaluation of the intellectual property rights of any party is guaranteed, and all technical and economic aspects are detailed. Therefore, OCM allows the seeker to involve solvers in defining a collection of open contract schemes, related to the supply of the required specific skills and technical knowledge. The solvers must submit offers in terms of contract versions of these contract schemes. In such a way, OCM aims at partially extracting from the solvers their multidimensional private information regarding economic and technical issues, in order to reduce the occurrences of pre- and post-contractual opportunistic behaviours. © 2012 Springer-Verlag Berlin Heidelberg

The repeated insertion model for rankings: Missing link between two subset choice models

Approval voting, probabilistic choice models, probabilistic ranking models, subset choice,