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Title: Zvi Wiener


1
Financial Risk Management
  • Zvi Wiener
  • 02-588-3049
  • http//pluto.mscc.huji.ac.il/mswiener/zvi.html

2
(No Transcript)
3
Breakfast
2 4 5 7 9 11 13 15
50 50
Lunch
50 50
? 11 ? ??
4
Correlation ?1
Breakfast
  • 2 4
  • 5 7 9
  • 11 13 15

50 50
Lunch
50 50
5
Correlation ?-1
Breakfast
  • 2 4
  • 5 7 9
  • 11 13 15

50 50
Lunch
50 50
6
Correlation ?0
Breakfast
  • 2 4
  • 5 7 9
  • 11 13 15

50 50
Lunch
50 50
7
Example
  • We will receive n dollars where n is determined
    by a die.
  • What would be a fair price for participation in
    this game?

8
Example 1
  • Score Probability
  • 1 1/6
  • 2 1/6
  • 3 1/6
  • 4 1/6
  • 5 1/6
  • 6 1/6

Fair price is 3.5 NIS. Assume that we can
play the game for 3 NIS only.
9
Example
  • If there is a pair of dice the mean is doubled.
  • What is the probability to gain 5?

10
Example
All combinations
  • 1,1 2,1 3,1 4,1 5,1 6,1
  • 1,2 2,2 3,2 4,2 5,2 6,2
  • 1,3 2,3 3,3 4,3 5,3 6,3
  • 1,4 2,4 3,4 4,4 5,4 6,4
  • 1,5 2,5 3,5 4,5 5,5 6,5
  • 1,6 2,6 3,6 4,6 5,6 6,6

36 combinations with equal probabilities
11
Example
All combinations
  • 1,1 2,1 3,1 4,1 5,1 6,1
  • 1,2 2,2 3,2 4,2 5,2 6,2
  • 1,3 2,3 3,3 4,3 5,3 6,3
  • 1,4 2,4 3,4 4,4 5,4 6,4
  • 1,5 2,5 3,5 4,5 5,5 6,5
  • 1,6 2,6 3,6 4,6 5,6 6,6

4 out of 36 give 5, probability 1/9
12
Additional information the first die gives 4.
All combinations
1,1 2,1 3,1 4,1 5,1 6,1 1,2 2,2 3,2 4,2 5,2 6,2 1,
3 2,3 3,3 4,3 5,3 6,3 1,4 2,4 3,4 4,4 5,4 6,4 1,5
2,5 3,5 4,5 5,5 6,5 1,6 2,6 3,6 4,6 5,6 6,6
1 out of 9 give 5, probability 1/9
13
Additional information the first die gives ?4.
All combinations
1,1 2,1 3,1 4,1 5,1 6,1 1,2 2,2 3,2 4,2 5,2 6,2 1,
3 2,3 3,3 4,3 5,3 6,3 1,4 2,4 3,4 4,4 5,4 6,4 1,5
2,5 3,5 4,5 5,5 6,5 1,6 2,6 3,6 4,6 5,6 6,6
4 out of 24 give 5, probability 1/6
14
Example 1
-2 -1 0 1 2 3
15
Example 1
  • 1 2 3 4 5 6 we pay
  • 1 2 3 4 5 6 7 6 NIS.
  • 2 3 4 5 6 7 8
  • 3 4 5 6 7 8 9
  • 4 5 6 7 8 9 10
  • 5 6 7 8 9 10 11
  • 6 7 8 9 10 11 12

16
PL
  • 1 2 3 4 5 6
  • 1 -4 -3 -2 -1 0 1
  • 2 -3 -2 -1 0 1 2
  • 3 -2 -1 0 1 2 3
  • 4 -1 0 1 2 3 4
  • 5 0 1 2 3 4 5
  • 6 1 2 3 4 5 6

17
Example 1 (2 cubes)
18
Example 1 (5 cubes)
19
Value
dollar
Interest Rate
interest rates and dollar are NOT independent
20
Regulation of Financial Intermediaries
  • take deposits, give loans
  • very small equity capital, big leverage
  • FDIC, CDIC, Israel - implicit
  • domino effect
  • Minimal capital requirements (8-9)

21
Banks
  • major increase of off-balance sheet in 80s
  • 1988 Basle accord (88 BIS Accord) -
    international minimum capital guidelines (credit
    risk).
  • 1996 Amendment - market risk VaR.
  • Amendment BIS 98

22
Accord Amendment
  • assets to capital ? 20
  • eligible capital/risk weighted assets ? 8
  • minimal capital charge for market risk
  • concentration risk
  • positions of 10 must be reported
  • positions of 25 need special permission

23
Accord Amendment
  • regulators encourage banks to develop models.
  • Banks must implement a RM infrastructure in
    their daily RM - limits, monitoring, etc.
  • G-30 report, 1993.

24
G-30 policy recommendations
  • The Role of senior management
  • Marking to market
  • Market valuation methods
  • Identifying revenue sources
  • Measuring market risk (VaR)
  • Stress simulation
  • Investing and funding forecasts

25
G-30 policy recommendations
  • Independent risk management
  • Practices by end-user
  • Measuring credit exposure
  • Master agreements
  • Credit enhancements
  • Promoting enforceability
  • Professional expertise

26
G-30 policy recommendations
  • Systems
  • Authority
  • Accounting practices
  • Disclosures
  • Recognizing netting
  • Legal and regulatory uncertainty
  • Tax treatment
  • Accounting standards

27
1988 BIS Accord
  • Developed by Basle committee
  • Accepted by G-10 Belgium, Canada, France,
    Germany, Italy, Japan, Netherlands, Sweden, UK,
    USA.
  • minimum asset to capital multiple
  • risk based capital ratio

28
1988 BIS Accord
  • risk based capital ratio - solvency ratio (Cooke
    ratio).
  • Capital divided by risk weighted on-balance-sheet
    assets plus off-balance-sheet exposures.
  • Weights are based on credit risk.
  • No netting or portfolio effects!
  • No market risk.

29
1988 BIS Accord
  • The Assets-to-capital multiple ? 20
  • Banks total assets divided by its total capital.
  • Some off-balance-sheet items, like letters of
    credit are accounted at nominal.

30
Weights in Cooke ratio
  • On-balance-sheet items
  • 0 Cash, gold, OECD government
  • claims, insured mortgages.
  • 20 OECD banks, OECD public sector
  • entities.
  • 50 Uninsured residential mortgages.
  • 100 All other claims.

31
Cooke ratio
  • Off-balance-sheet credit equivalent.
  • 1. Nonderivative exposure - conversion factor is
    set by regulators between 0 and 1.
  • 2. Derivative exposure Current replacement cost
    Add-on amount

Risk weighted amount ?AssetsW?Credit
equivalentW
32
Cooke ratio
  • Banks are required to maintain capital equal to
    at least 8 of their total risk weighted assets.
    (In Israel 9.)

33
Capital
  • Tier 1. Stock equity, preferred stock, minority
    equity interest in consolidated subsidiaries,
    less goodwill and other deductions.
  • Tier 2. Cumulative perpetual preferred shares,
    99 year debentures, some subordinated debt (?5y).
  • Tier 3. Can be used to cover market risk only.
    Short term subordinated debt (?2y).
  • Tier 1 Tier 2 ? 8, and Tier 1 must be at
    least 50 of this amount.

34
Models
  • Standard model.
  • Internal models (based on VaR).
  • (3marketVaR10d 4creditVaR10d)trigger/8
  • trigger 8 in North America and between 8 and 25
    in the UK

35
Problems with the current approach
  • No distinction between a loan of 100 and 100
    loans of 1 each one.
  • Turkish bank has lower capital requirements than
    General Electric.
  • A loan to AA rated firm is treated as a loan to
    a B rated firm.
  • Some similar contracts are treated differently.

36
New proposals
  • BIS 2000
  • VaR based approach to credit risk.
  • CreditMetrics
  • CreditRisk
  • KMV
  • Merton.

37
New Approach
  • Three pillars
  • A. Minimum Capital Requirement
  • B. Supervisory Review Process
  • C. Market Discipline Requirements

38
What is the current Risk?
  • duration, convexity
  • volatility
  • delta, gamma, vega
  • rating
  • target zone
  • Bonds
  • Stocks
  • Options
  • Credit
  • Forex
  • Total ?

39
Standard Approach
40
Modern Approach
Financial Institution
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