ts M (ít hơn chi phí đầu tư nếu nó đã được thực hiện trong giai đoạn 1). Nếu đương nhiệm thừa nhận để thách thức sau đó họ chia sẻ thị trường và từng được J. Nếu đầu tư không thực hiện thì chi phí của ghting . | 374 CHAPTER 11. INFORMATION always necessary to introduce quite strong assumptions about the structure of preferences and technology. In virtually every case we have used the singlecrossing condition for different families of indifference curves in order to find a tractable solution and to be able to draw interpretable conclusions from the analysis. Finally let us remind ourselves of some common curiosities that emerge from imperfect-information models. The possible multiplicity of equilibria - as in the signalling models section . It is not clear that intellectual devices to reduce this plethora are entirely convincing. More disturbing perhaps is the possible lack of equilibrium in some cases see the model of the insurance market section and some signalling models Exercise . The use of rationing and price distortions to force a second-best solution where imperfect information means that first best just cannot be implemented. We will see that some of these features will be particularly relevant for our discussion of the problem of economic design. Reading notes Good introductions to the economics of information and the theory of contracts are provided in Macho-Stadler and Pérez-Castrillo 1997 and in Salanié 1997 . An overview of the issues is provided by Arrow 1986 . The classic reference on adverse selection screening and the economics of insurance markets on which subsection is based is Rothschild and Stiglitz 1976 . The classic papers on the economics of signalling are Akerlof 1970 and Spence 1973 . The intuitive criterion is attributable to Cho and Kreps 1987 . The case of costless signals - so called cheap-talk models - is treated in Crawford and Sobel 1982 . A good introduction is in Salanié 1997 pages 95ff on which the example in section is based. For an introduction to the Principal-and-Agent model see Ross 1973 and for a thorough treatment refer to Laffont and Martimort 2002 . The classic papers are Holmstrom 1979 and .
