Portfolio Management Flashcards
Value at Risk (VaR)
Minimum loss that would be expected a certain percentage of time over a certain period of time
5% VaR = 1.65 standard deviations
1% VaR = 2.33 standard deviations
16% VaR = 1 standard deviation
Scenario Analysis
Compared to Sensitivity analysis (single risk factor), provides an estimate of the impact on portfolio value of a set of changes in magnitude in multiple risk factors
Computes value of an investment under a finite set of scenarios (e.g. best case, worst case, most likely case) and performance of portfolio under conditions of market stress
used when distribution of risk is discrete and can accommodate for correlated variables
E.g., stress tests or reverse stress tests
Sensitivity Analysis
Focuses on the impact on value of a given small change in one risk factor
Complementary to VaR in understanding portfolio risk
Used to estimate how gains and losses in the portfolio change with changes in the underlying risk factors
Statistical Factor Models
Advantages:
- Makes minimal assumptions
Disadvantages:
- Interpretation is generally more difficult than interpretation of macroeconomic or fundamental factor models
Elements of a VaR Statement
VaR statement contain elements of:
- Minimum loss
- Defined time period (frequency of losses)
- Stated probability of risk (tied to normal distribution confidence levels e.g. 5% VaR = 95% confidence level)
Define Sharpe Ratio and how to calculate it
Sharpe ratio provides a measure of how much the investor is receiving in excess of a risk less state
used to compare the portfolio return in excess of a risk less rate with the volatility of the portfolio return
Unaffected by the addition of cash or leverage in a portfolio
SR = Rp - RFR / STD(Rp)
RP = portfolio return STF(Rp) = Standard deviation of portfolio return
Information ratio
Can be thought of a way to measure consistency of active return, which is what investors prefer
It IS impacted by leverage and cash
What is the formula for calculating variance of portfolio return?
(Weight Asset A)^2 * (variance of asset A) + (Weight Asset B)^2*(variance of asset B) + 2(WB)(WA)(CovAB)
How many trading days are there in a year?
250 trading days
List out the weaknesses of the Parametric method for calculating VaR
Estimates are only as good as the inputs
Length of look back period will affect the parameter estimates
Limited usefulness when normality cannot be reasonably assumed
What are strengths and weaknesses of using historical simulation to estimate the VaR?
Strengths:
You don’t need to assume a distribution
Method can be used to estimate VaR of a portfolio that includes options (i.e. need not worry about normality)
Weakness:
Using a highly volatile (stable) look back period can yield overestimate (underestimate) of VaR
What are the characteristics of estimating VaR using Monte Carlo simulation?
First and important key step is assuming a probability distribution of and correlations between each risk factor
Similar to historical simulation, VaR estimated from sorted outcomes
**Monte Carlo and parametric methods should yield identical results if the distribution and parameters are the same
Advantages of VaR
Concept is easy to explain
Allows the risk of different portfolios and asset classes to be compared
Can be used for performance evaluation
Used in optimal allocation of capital (i.e. risk budgeting)
Verified via backtesting
Widely accepted amongst global banking regulators
What are the limitations of VaR?
Estimation requires many choices
Assumptions of normality lead to underestimation of downside (Tail) risk
Does not account for liquidity risk or changing correlations
Focuses only on downside risk
What is an ETF?
Tracks an Index and trades on a secondary market
Market Makers are known as Authorized Participants (AP) who are authorized to create new or redeem existing shares
ETF manager/sponsor will define the list of securities that are needed to create new shares or creation unit
What are the advantages of ETF?
Lower cost - The in-kind creation/redemption eliminates transaction cost
Tax Efficiency - creation/redemption is not a taxable event; ETF sponsor may specify low basis stock as part of the redemption basket
Market Prices in line with NAV - APs can arbitrage any price discrepancy
What is an arbitrage gap?
Difference between price of ETF share and the NAVPS. APs can profit from price discrepancy by creating (redeeming) shares if the arbitrage gap is less (more) than the difference between price of ETF and NAV.
Arbitrage gap varies with transaction costs and service fees payable to ETF manager and the timing difference between when ETF trades and when underlying securities trade (due to time zone diff for foreign securities)
illiquid (liquid) securities have higher (lower) transaction costs and hence higher (lower) arbitrage gaps
What is Tracking Error?
Tracking difference between NAV and benchmark return (annualized standard deviation of the daily tracking difference)
What are the sources of tracking error?
- ETF fees and expense
- Sampling & Optimization
- Depository receipts/other sector ETFs
- Index changes
- Reg & Tax requirements
- Fund accounting practices
- Asset manager operations
How to calculate the holding cost to the ETF investor?
Round-trip commission refers to the cost associated with buying and selling the ETF
Round-trip trading cost = round-trip commission fees + bid-ask spread
Total cost = round-trip trading cost + management fees (mgmt fees are relevant for long-term buy and hold investors)
What are the risks associated with ETFs?
- Counterparty risk
Exchange traded notes (ETNs)
Settlement risk
Security lending - Fund Closure - Hard close refers to full liquidation with negative tax consequences to the investor (ideally); Soft close refers to creation/redemption halts and slowly unwinds
- Expectation-related risk (10% gain is not the same as 10% loss)
Uses of an ETF in portfolio management
- Liquidity management
- Rebalancing
- Portfolio completion
- Transition management
Asset class exposure management
- Core exposure
- Tactical strategies
Active ETF strategies are most likely to be used for?
Mostly for fixed income rather than equity given the lower liquidity. These are suitable for long-term buy and hold investors as they seek to beat the benchmark and therefore tracking risk is expected to be higher for active ETFs than for passive ETFs
What is the arbitrage pricing theory (APT)?
Describes the equilibrium relationship between E(R) for well-diversified portfolio and their multiple sources of systematic risk (i.e. risk that cannot be diversified away)
What are the assumptions of APT?
- Unsystematic risk can be diversified away
- Returns are generated using a factor model (there is a lack of clarity on how to identify risk factors)
- No arbitrage opportunities exist (implies investors will take take large positions to exploit any perceived mispricing resulting in asset prices to adjust immediately)
APT formula
E(Rp) = Rf + (Sensitivity factor x factor risk premium)1…
what is the Macroeconomic Factor Model?
This model assumes asset returns are explained by surprises in macroeconomic risk factors (e.g. GP, interest rates, inflation). Factor surprises are defined as the difference between realized value and predicted value
what is the fundamental factor model?
This model assumes asset returns are explained by factors specific to the firm (e.g. P/E ratio, market cap, earnings growth rate). Factors are returns and not surprises (like macroeconomic factor model)
Factor sensitives are standardized (betas are like z-scores)
what are some differences between macro and fundamental factor models?
- Macro models are time-series of surprises whereas fundamental models are cross-sectional asset returns
- Macro model beta (factor sensitivity) is regression based whereas fundamental models is standardized (z-score)
- Macro model factor returns are surprises in macro variables whereas fundamental models is computed from multiple regression
Define active return
Active return is the difference between the portfolio return and its benchmark
Rp-Rb
Define active risk/tracking risk
It is the standard deviation of active return. It can be calculated as:
Tracking error = sq.rt. [{summation(active return)^2}/n-1]
What does information ratio measure and how do you calculate it?
It measures active return per unit of active risk - i.e. a managers’s consistency in generating active returns. The higher the better.
It can be calculated as:
IR = (Avg Rp - Avg Rb) / active risk/tracking error
What are the sources of active return?
Active return = factor return + security selection return
what is the decomposition of active risk?
Active risk squared -> active factor risk + active specific risk; where:
- Active factor risk is attributable to factor tilts
- Active specific risk is attributable to stock selection
And active specific risk = [Summation (Wp - Wb)^2] * residual