Contract_theory_Notes_1.pdf - Markets with asymmetric information and contract theory Ivan Susin [email protected] Higher School of Economics St-Petersburg

# Contract_theory_Notes_1.pdf - Markets with asymmetric...

• Notes
• 10

This preview shows page 1 - 3 out of 10 pages.

Markets with asymmetric information and contract theory Ivan Susin, [email protected] Higher School of Economics, St-Petersburg, Russia 1 Formal issues The grading formula: 1 , 6 + 2 , 8 + 2 , 8 + 2 , 8 + [1] First homework will be due November 24th 23:59 Second homework will be due December 8th 23:59 Late submissions will receive 50% penalty. Homeworks are to be typeset in L A T E X(I recommend using overleaf.com , it works really smoothly) and submitted to e-mail. Handwritten papers are incredibly hard to read and formulas typeset in Word are not much better. I’ll provide a template along with the problem set itself. Tests will be given on the lectures. First one will be given on 20th November. Second one will be given on 4th of December. 2 Dictionary 2.1 Letters and symbols. θ “theta” (usually pronounced ’тэта’ in Russian) usually denotes a type. μ (’мю’), ρ (rho, ’ро’), λ (lambda, ’лямбда’) or rarely η (eta ’эта’) and ν (nu, ’ню’) denote probabilities and beliefs. As usual, p refers to price, U to utility (when principal is the firm, π is the profit), C - to costs. 1

Subscribe to view the full document.

Indexes: i - is our usual generic type. j - one of other types, ( - i ) - all other types. Over-line, underline or number ( ¯ θ , θ , θ 1 ) denotes particular type. 2.2 Terms Binding constraint - the one that is equality, we cannot maximize further the terms in it without violating it. Non-binding constraint - there is strict inequality, this constraint currently does not affect equilibrium. Principal-agent framework. Both are a gents, only Agent is A gent. Principal moves first and proposes the contract (or menu of contracts ). She maximizes her utility over all possible contracts, so it is usually our job to understand what contracts are possible given the problem. Then we have to select the contract that is best for her and is possible. Agent chooses to sign or not to sign a contract or, if there is a menu of contracts, chooses particular one. There are different types of agents. Type is a game-theoretic idea that captures all the information that agent has. We might have from just two types to uncountable continuum of types (if private information is a number in [0 , 1] or R , for example). Those types may be publicly known - situation that is usually known as “First Best” or FB, because usually it is the simplest and Pareto-better than otherwise. If only the Agent (not the principal) knows his type for sure, we are in the “Second Best” world (and we usually are). In SB principal still can propose something to induce the Agent to reveal the information. There is an important idea, called “revelation principle” , that roughly says that if the principal can commit to the contract (to make it irrevocable once the Agent reveals information), any contract can be written in a way where Agent is truthful. Here a little trick happens - space of possible contracts is weird and may be hard to describe. This problem will be discussed in more detail in mechanism design course, in particular “implementation theory” is devoted to this issue. For now we’ll explicitly fix set of contracts to be linear
• Fall '15
• Medvedeva

### What students are saying

• As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

Kiran Temple University Fox School of Business ‘17, Course Hero Intern

• I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

Dana University of Pennsylvania ‘17, Course Hero Intern

• The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

Jill Tulane University ‘16, Course Hero Intern