The experimental analysis of multi-attribute auctions in chapter 6 provides a good understanding of the relevant issues and causalities. This chapter will focus more on the theoretical underpinnings of multi-attribute auctions. So far, game-theoretical models have focused on cases in which agents' private information is one-dimensional. The consideration of multidimensional types poses substantial technical difficulties and results of any generality seem restricted to a few papers. The complications are not merely technical: many economic insights in single-dimensional theory do not necessarily extend in any natural fashion.

Section 7.1 will provide a summary of spare game-theoretical literature in this field. Section 7.2 will compare the results of conventional and multiattribute auctions using a simulation model. This section will also consider the particularities of OTC trading of financial derivatives, which have been the focus in chapter 6. Up until this stage quantity was assumed to be fixed in advance and all items to be purchased from a single bidder. Section 7.3 will provide a classification framework for multi-attribute auctions where quantity is an issue, and introduce a model which shows the impact of economies of scale on the outcome of multi-attribute auctions.