1. Marek Kapicka Lecture 15 Financial Intermediation
Econ 208
Marek Kapicka
Lecture 15
Financial Intermediation

2. Announcements
PS5 will be posted today, due next Thursday before the section (3pm)
Give them directly to Xintong, or to her mailbox
Read “Zero sum debate” – the Economist article about capital taxation

3. Why Financial Crises?
Key insight: Banks are here to transform illiquid assets to liquid liabilities
Depositors prefer to withdraw deposits easily (preference for liquidity)
Borrowers need time to repay the loans
Tension between both sides of the balance sheet:
If everyone wants to withdraw deposits, there is not enough resources

4. A Liquidity Problem How to choose between liquid and illiquid assets?
Liquid assets: can be converted into immediate consumption without any costs
Illiquid assets: it is costly to convert them into immediate consumption
People have preference for liquidity: they are unsure when they need to consume

5. A Liquidity Problem Timing

6. A Liquidity Problem Preferences

7. An Example of Early Consumers

8. A Liquidity Problem Preferences

9. A Liquidity Problem Autarkic Solution Market Solution
Efficient Solution
Banking Solution

10. 1. Autarkic Solution

11. 1. Autarkic Solution The Budget Constraint

12. 1. Autarkic Solution

13. A Liquidity Problem Autarkic Solution Market Solution
Efficient Solution
Banking Solution

14. 2. A Market Solution Market vs. Autarky
In a market, early consumer are allowed to sell long assets and buy short assets
We don’t have time to go through this, but one can show:
Market can achieve more risk sharing than autarky
We will see that with banks we can do even better than that

15. 2. A Market Solution Market vs. Autarky
Market Equilibrium
Autarkic choices

16. A Liquidity Problem Autarkic Solution Market Solution
Efficient Solution
Banking Solution

17. 3. The Efficient Solution What is efficiency?

18. 3. The Efficient Solution Social planner’s problem
Maximize the expected utility
Subject to
WLOG assume that late consumers only consume in period 2

19. 3. The Efficient Solution Social Planner’s problem
Maximize the expected utility
First order condition

20. 3. The Efficient Solution Case 1: Too little liquidity in the market solution
Market Equilibrium
Efficient Solution

21. 3. The Efficient Solution Case 2: Too much liquidity in the market solution
Market Equilibrium

22. 3. The Efficient Solution Case 3: The right amount of liquidity in the market solution
Market Equilibrium
= Efficient solution

23. 3. The Efficient Solution What next?
In general, the market solution is not efficient
How to get efficiency?
Can banking improve on the market solution?

24. A Liquidity Problem Autarkic Solution Market Solution
Efficient Solution
Banking Solution

25. 5. Banking Solution A note on Information Structure

26. 5. Banking Solution

27. 5. Banking Solution Equilibrium without runs
Later on, we’ll see that banks are prone to runs, but ignore it for now
The bank maximizes the expected utility
Subject to

28. 5. Banking Solution Equilibrium without runs
Maximize the expected utility
First order condition
Identical to the social planner’s problem
The (good) equilibrium is efficient!

29. 5. Banking Solution Equilibrium without runs

30. 5. Banking Solution Equilibrium without runs
Equilibrium without runs

31. 5. Banking Solution Equilibrium with runs

32. 5. Banking Solution Equilibrium with runs
Suppose that everyone decides to withdraw in period 1
Since
Not everyone in can be paid in period 1
Those who wait until period 2 will get nothing
The bank will become insolvent

33. 5. Banking Solution Equilibrium with runs
A payoff matrix: late consumer (rows) vs every other late consumer (columns):
Note: the run/run payoff is the expected payoff
There are two equilibria:
No run/No run (good equilibrium)
Run/Run (bad equilibrium)
Run
No Run