RISK MANAGEMENT AS A PROCESS ranges for exposures, measurement of these exposures & the execution of appropriate adjustments when required.. Risk management process to a hypothetical bus
Trang 1“ RISK MANAGEMENT ”
1 INTRODUCTION
Identification, measurement & control of risk are key to the investment process
Risk management framework is applicable to the management of both enterprise & portfolio risk
Indentify which risks are worth taking on a regular or occasional basis & which should be avoided altogether
2 RISK MANAGEMENT AS A PROCESS
ranges for exposures, measurement of these exposures & the execution of appropriate adjustments when required
Risk management is a continuous processes (subject to evaluation & revisions) not just an activity
Risk management process to a hypothetical business enterprise:
Set Policies &
Procedures
Define Risk Tolerance
Identify Risks
Measure Risks
Adjust Level
of Risk
Execute Risk Mgmt
Transactions Identify Appropriate Transactions
Price Transactions
Execute Transactions
Derivatives
Non-Derivatives
Uncertainty
Select Appropriate Model
Determine Market Price or Value
Determine Model Price or Value
Compare
Transaction
RG = Risk Governance
ERM = Enterprise Risk
Management
CG = Corporate Governance
DB = Defined Benefit
ESG = Environmental, Social
Governance
VAR = Value at Risk EAR = Earning at Risk
CR = Credit Risk
IR = Information Ratios RAROC = Risk-Adjusted Return on Capital
Trang 22 RISK MANAGEMENT AS A PROCESS
Risk management process to portfolio management:
Companies hedge risk that arise from areas in which they have
no expertise or comparative advantage &hedge tactically where they have an edge (e.g primary line of business)
Risk management involves risk modification
3 RISK GOVERNANCE
RG ⇒process of setting overall policies & standards in risk management is called RG
RG is of good quality if it is transparent, effective, efficient &
accountable
Risk Governance Structure
Single risk management group to monitor & control the risk
Also called ERM or firm wide risk management
Risk management by individual business unit managers
Benefits
Economies of scale
Allows a company to recognize the offsetting nature of distinct exposures
Enterprise-level risk estimates may be than individual units (risk-mitigating benefits of diversification)
Consider each risk factor to which a firm is exposed (in isolation & in terms of any interplay)
Benefit
People closer to actual risk taking are allowed to manage it
Effective RG is possible only if the organization has effective CG
Steps in effective ERM system:
Identify individual risk factors
Quantify exposure in monetary term
Use these inputs to a risk estimation model (e.g VAR)
Indentify overall risk exposures & contribution from each risk factor
to overall risk
Process of risk reporting to senior management
Monitor compliance with policies & risk limits
Effective ERM systems have centralized data warehouses which may require a significant & continuing investment
Trang 34 IDENTIFYING RISKS
Effective risk management requires the separation of risk exposures into specific categories that reflect their distinguishing characteristics
Accounting Taxes
Legal
Regulations
Settlement
Operations Model
Liquidity Risk
Market Risk (interest rate, exchange rate, equity prices & commodity prices risk)
4.1 Market Risk
Market risk is linked to supply & demand in various marketplaces
DB plan measures market exposure in asset/liability management context
4.2 Credit Risk
Development of credit derivatives has blurred the lines b/w credit risk & market risk
Before OTC credit derivative recognition, bond portfolio managers & bank officers were the primary credit risk managers
4.3 Liquidity Risk
potential inability to efficiently accommodate the desired trading size
In case of short squeezing, liquidity may completely dry up in the market
For illiquid underlying, derivatives market may also be illiquid
Size of the bid-ask spread is an imprecise measure of liquidity risk (because it is suitable only for small trade size)
Complex liquidity measures are available to address the issue of trading volume
Liquidity risk is difficult to observe & quantify
Trang 44.4 Operational Risk
external events
The risk can arise from:
Human errors (unintentional errors or willful misconduct)
Computer breakdown (hardware, software problems)
Act of God (only cash compensation for losses can be covered through insurance)
unauthorized transactions or some combination of both
Companies manage operational risk by monitoring their systems, taking preventive actions & having a plan in place to respond if such events occur
4.5 Model Risk
Inappropriate model ⇒ chances of loss & control over risk is impaired
Investors must scrutinize & validate all models they use
4.6 Settlement (Herstatt) Risk
while the counterparty is announcing bankruptcy
Transactions b/w exchange members & clearing house removes settlement risk
Netting arrangement reduces settlement risk
Transactions with foreign exchange component:
Don’t lend themselves to netting
Parties are unaware to each other
The risk is called Herstatt risk (bank Herstatt default)
Risk can be mitigated through continuously linked settlement (simultaneous payments)
4.7 Regulatory Risk
Risk associated with the uncertainty of how a transaction will be regulated or potential for regulation change
Regulation is a source of uncertainty (risk that existing regulatory regime will ∆ or unregulated market will become regulated)
Regulatory risk is difficult to estimate due to ∆ in political parties & regulatory personnel
Equivalent combinations of cash & derivative securities are not regulated by same way
or by same regulator
4.8 Legal/Contract Risk
contract in which an enterprise has a financial stake
Dealers should be very careful when writing contracts with their counterparties (due to their advisory nature)
Contract law is often federally or nationally governed
4.9 Tax Risk
Uncertainty associated with tax laws
Tax policy often fails to keep pace with innovations in financial instruments
Equivalent combination of financial instruments may be subject to different tax treatments
Trang 54.10 Accounting Risk
Uncertainty about transaction recording & potential for accounting rules & regulations
to ∆
Historically accounting standards varied from country to country (more disclosure requirements in some countries than others)
Accounting risk can be reduced by hiring personnel with latest accounting knowledge (accounting risk will always remain)
4.11 Sovereign and Political Risks
Sovereign risk;
Form of credit risk involving sovereign nation’s borrowing
Current credit risk & potential credit risk
Its magnitude involves likelihood of default & the estimated recovery rate
Willingness & ability to repay
Political risk ⇒ risk of ∆ in the political environment
4.12 Other Risks
Environmental risk ⇒ leads to variety of –ve financial & other
consequences
Social risk ⇒ risk regarding policies & practices of human
resources, contractual arrangements & work-place
Performance netting risk;
Applies to firms that fund more than one strategy
Firm will receive fee only if net +ve performance
Firm will pay its portfolio managers on basis of individual performance
Asymmetric incentive fee arrangements with portfolio managers
Firms may have to pay to its portfolio managers when firm’s revenue is zero
Settlement Netting Risk
Risk of netting arrangement on profitable transactions for the benefit of creditors challenged by liquidator of counterparty in default
Risk is mitigated by netting agreements that can survive legal challenge
5 MEASURING RISK
Exposure of actively traded financial instruments prices to ∆ in IR, exchange rates, equity prices & commodity prices
Volatility (S.D) is a statistical tool to describe market risk
Adequate description of portfolio risk
Suitable for instruments with linear payoffs
Portfolio’s exposure to losses due to market risk:
Primary or 1st order measures of risk ⇒ adverse movement in a key variable (linear)
2nd order measures ⇒ ∆ in sensitivities (curvature)
Examples of primary risk measures are β (for stocks), duration (for bonds) & delta, vega &
theta (for options)
Examples of 2nd
order measures are convexity & Gamma
5.1 Measuring Market Risk
Trang 65.2 Value at Risk
Probability-based measure of loss potential for a company, fund, portfolio, strategy
or transactions
Expressed either in % or in units of currency
Easily & widely used to measure loss from market risk but can also be used to measure credit & other exposures (subject to greater complexity)
Can be described as a minimum or maximum VAR
It measures a minimum loss
The probability, the VAR in magnitude
VAR has a time element (the period, the VAR)
5.2.1 Elements of Measuring Value at Risk
Establishing an appropriate VAR measure requires
a no of decisions about the calculation structure
Three Important Decisions in VAR
The probability, more conservative the
VAR estimate is
Linear risk characteristics portfolios, two
probability level (e.g 5% & 1%) will
provide identical information
Optionality or nonlinear risks, select the
more conservative probability threshold
VAR magnitude is directly related to time interval selected
Relationship is nonlinear
Three standardized methods for estimating VARs (discussed below)
5.2.2 The Analytical or Variance-Covariance Method
Assumptions ⇒ portfolio returns are normally distributed
Standard normal distribution ⇒ expected value of zero & a SD of 1
Conversion of a nonstandard normal distribution to a standard normal distribution:
= ^−
Estimation of expected returns & SD of returns is key to using analytical method
If we are comfortable with normal distribution assumption & accuracy of our estimates, we can confidently use the analytical method for a different time period by adjusting the avg returns & SD accordingly (e.g annual VAR can be converted to daily VAR by dividing avg return & SD to 250 (trading days))
VAR (usually daily VAR) can also be estimated by assuming an expected return of zero Two advantages:
No need to estimate E(R) which is harder to estimate than volatility
Easier to adjust VAR for a different time period( = √250)
Advantage/Disadvantage of Analytical Method
Simple method Normal distribution assumption often
does not hold (e.g.in options)
Trang 75.2.3 The Historical Method
Collect the historical return & indentify the return below which 5% or 1% of returns fall
No constraint to use normal distribution
If different portfolio composition than what actually had in the past to calculate historical VAR, it is more appropriate to call the method a historical simulation
not so acute)
5.2.4 The Monte Carlo Simulation Method
MCS produce random portfolio returns which are assembled into a summary distribution from which we can determine at which level the lower 5% (or 1%) of return outcomes occur
MCS does not require a normal distribution
MCS is more flexible approach & even suitable for portfolios containing options
As sample size sample VAR converge to population VAR
MCS require extensive commitments of computer resources
5.2.5 Surplus at Risk": VAR as It Applies to Pension Fund Portfolios
Pension fund managers apply VAR methodologies to the surplus (rather their asset portfolio)
Managers express their liability portfolio as a set of short securities & calculate VAR on net position (any VAR methodology can apply)
5.3 The Advantages and Limitations of VAR
Can be difficult to estimate
Different estimation methods can provide different
results
If assumptions are not accurate, VAR often
underestimate magnitude or frequency of worst returns
Portfolio VAR is not simply the sum of individual
position’s VAR
VAR provide incomplete picture of overall exposure
(ignore +ve results)
Back testing should be applied to check method’s
accuracy
VAR estimate is not suitable for organization with
complex structure
VAR’s Imperfections
Quantify loss in simple terms
Easily understood by senior management
May be a requirement of regulatory body
VAR is a verstyle measure
VAR is often paired with stress testing
VAR results are input dependent
VAR’s Attractions
Trang 85.4 Extensions and Supplements to VAR
an asset
Provide extremely limited picture of the asset’s or portfolio’s contribution to risk
Cash flow at risk & EAR ⇒ with a given probability & over a specified time period, the minimum CF (earnings) that we expect to be exceeded
Useful for companies that generate CF or earnings but not readily valued in a publicly traded market
additional loss occurs
5.5 Stress Testing
Stress testing is used to supplement VAR as a risk measure
VAR assumes potential losses under normal market conditions while stress testing identifies additional losses due to unusual circumstances
Approaches in Stress Testing
Evaluating a portfolio under different scenarios
Effect of large movements in a key variable on portfolio’s value
force (e.g IR, exchange rate etc.)
sequential fashion (in reality shocks often happen simultaneously)
resulting from the events that occurred in the past
to analyze & confusing outcomes)
When a series of appropriate scenarios is established, the next step is to
apply them to the portfolio (consider assets’ sensitivities to the underlying
risk factors)
5.5.1 Scenario Analysis
Use an existing model & apply shocks to the model inputs in some mechanical way
Range of possibilities rather than a single set of scenarios
Computationally demanding
way & to work out the combined effect on the portfolio value
Model risk is present
will produce the maximum loss
5.5.2 Stressing Models
5.6 Measuring Credit Risk
CR has two dimensions:
Probability of loss
Amount of loss
Empirical data set on credit losses is quite limited with respect to time perspective, credit losses can be current or potential credit losses
Credit VAR can’t be separated from market VAR & focus on upper tail of the distribution of market returns
More accurate measures of default probability & recovery rate ⇒ & more accurate credit VAR
Estimating credit VAR is complicated because:
Credit events are rare & harder to estimate
CR is less easily aggregated than market risk
Correlations b/w CR of counterparties must be considered
Trang 95.6.1 option-Pricing Theory and Credit Risk
A bond with CR can be viewed as:
Default free bond plus
Short put option written by bondholders for shareholders (this put option reflects shareholders right of limited liability)
Traditional put-call parity with a little bit changes can be used to draw value of implicit put option
Value of put option is the difference b/w default-free bond & bond subject to default
5.6.2 The Credit Risk of Forward Contracts
Each party assumes the other’s CR
No current CR exists prior to expiration (no payments are due)
If the counterparty with –ve value declares bankruptcy before the contract expiration, the claim of non-defaulting counterparty is market value of forward contract at the time of bankruptcy
5.6.3 The Credit Risk of Swaps
CR is present at a series of points during the contract’s life
MV of contract can be calculated at any time to reflect potential CR
CR of IR & equity swaps is largest during middle of swap’s life
In case of currency swaps, the CR is greatest b/w midpoint to end of swap’s life
5.6.4 The Credit Risk of options
Options have unilateral CR (after paying premium credit risk accrues entirely to the buyer)
Credit risk on derivative transaction tends to be quite small relative to that on loan
5.7 Liquidity Risk
Cost of an illiquid instrument can be measured through bid-risk spread
Instruments that trade very infrequently at any price give illusion of volatility)
Practitioners often liquidity-adjust the VAR estimates
5.8 Measuring Non-Financial Risks
These risks are very difficult to measure ⇒ usually lack of observable distribution
of losses related to these factors
Techniques like extreme value theory is used if possible to model sources of risk but these techniques are input dependent
5.8.1 Operational Risk
Well publicized losses at financial institutions (e.g rogue employees theft) have put operational risk justifiable into the forefront
Banks can measure their operational risk through Basel II
5.6.1 Option-Pricing Theory and Credit Risk
Trang 106 MANAGING RISK
Effective risk governance model
Systems & technology to provide timely & accurate risk information decision makers
Trained personnel to evaluate risk information
Risk management is just a good common business sense
6.1 Managing Market Risk
ERM system identifies appropriate risk tolerance levels
Taking too little risk is as much problematic as taking too much risk (e.g possible rewards)
6.1.1 Risk Budgeting
Risk budgeting ⇒ efficient allocation of capital risk across various units of an organization or portfolio managers
Risk Budgeting
Allocation of an acceptable level of risk to various departments of an organization
In addition to VAR, risk can also be allocated based on individual transaction size, amount
of working capital needed etc
If correlation among departments is < 1, the sum of risk budgets for individual units >
than organizational risk budget
Assets class correlation adjusted IR can determine the optimal tracking risk allocation
Investment manager’s allocation is positively related to his correlation adjusted IR
Risk budget allocation should be measured in relation to risk to surplus (assets – liabilities)
6.2 Managing Credit Risk
Estimating default probability is difficult
Credit risk is not symmetric & normally distributed (downside only) thus not easily measured & controlled using SD & VAR
Not lend too much money to one entity
Not engage in too many derivative transactions with one counterparty
6.2.2 Reducing Credit Risk by Marking to Market
Credit risk can be reduced through marking to market an OTC derivative contract
OTC options are not marked to market (one sided +ve value)
Credit risk of option is normally handled by collateral