Measurement of Risk
Analysis of Risk & Uncertainty¶
Description & Measurement of Risk¶
Risk¶
- Variability in actual returns wrt \(E(r)\), in terms of cashflows1.
Sensitivity Analysis (Absolute measure)¶
- How sensitive estimated project parameters are to estimation errors
- Parameters: cash flows, cost of capital, economic life
- Estimates made under three assumptions: pessimistic, most likely, optimistic
- Example 1: Calculate NPV of Project \(X,Y\) for each possible cash flow (worst, most-likely, best) using sensitivity analysis
- NPV determination
- conservative and risk-taking attitude towards risk
Assign probabilities¶
- Drawback of sensitivity analysis: Doesn't disclose the chances of occurrence of these variations
- Example 2: Find expected return on the project. PV of expected monetary values.
Scenario Analysis (Absolute measure)¶
- Evaluate the impact on the project's profitability of simultaneous changes in more than one variable at a time (inflows, outflows, cost of capital)
- Ask operating manager (production, sales, personnel)
- worst-case (high fixed costs, high VC, low Selling price, low sales volume, higher cost of capital) etc.
- best-case - vice versa
- NPV guides the decision and helps assess the risk
- Highly unlikely (both the scenarios), but useful \(\implies\) If NPV positive in worst case, then project is worth accepting.
- Limited Usefulness: Considers few discrete outcomes, infinite number of possibilities exist
- Ask operating manager (production, sales, personnel)
Simulation¶
- get a feel of the risk (statistics based)
- Apply predetermined probability distributions + random numbers \(\implies\) estimate risky outcomes
Precise Measures of Risk: Standard Deviation and CoV¶
Standard Deviation (Absolute measure)¶
CoV (Relative measure)¶
- Example 4: Compare the risk of projects on the basis of SD and CoV
Risk Evaluation Approaches¶
1. Risk-adjusted Discount Rate Approach (RAD)¶
- relatively risky \(\implies\) relatively high discount rates
- Accept-reject Decision
- NPV and IRR approach
- -ve NPV \(\implies\) Reject
- internal rate of return, \(r \gt\) risk-adjusted rate \(\implies\) Accept
- Example 5: Evaluate project (accept/reject)
- Evaluation (+1 -3)
- + Simple to calculate
- - How to determine risk-adjusted discount rate?
- - Doesn't use direct info available distribution of expected future CF, it adjust \(r\) instead of CF
- - Risks compounds overtime, not theoretically desirable into practice. Discounting process should only consider time value and not risk.
2. Certainty-Equivalent Approach¶
- We adjust the expected cash flow directly.
- Risk-adjustment factor is expressed in terms of a certainty-equivalent coefficient \(a_{t}\)
- Based on firm's utility preference: \((12000) \sim (20000,0.6)\)2
- This coefficient \(a = 0.6\) when multiplied to a risky CF gives us a riskless CF
- \(a\propto \dfrac{1}{\text{Risk}}\)
Accept-Reject Rule
- Illustration using Example 5
- Evaluation (+2 -1)
- + simple to calculate
- + modifies CF that is subject to risk
3. Probability Distribution Approach¶
- Dependent CF
- Independent CF
-
You are essentially finding \(Var\left(\dfrac{CF}{(1+i)^t}\right)\)
-
Where \(\sigma_{t} = \sqrt{ \sum (CF_{jt} - \bar{CF_{t}})^2 \cdot P_{jt}}\)
Problem Checklist
- Example 6: Expected Cashflow and standard deviation
- Normal distribution: (\(\leq 0, \gt 0, a \lt CF \lt b\))
- Example 7: Find probabilities (i) \(\leq 0\); (ii) \(\gt 0\); (iii) \((25,45)\); (iv) \((15,30)\)
- Example 8:
- (i) \(\mu = E(NPV)\);
- (ii) \(\sigma_{NPV}\) ;
- (iii) \(P(NPV\dots)\) :
- (a) \(\leq 0\); (b) \(\gt 0\); (c) \(\geq \mu\)
- (iv) Profitability Index of \(\mu\);
- (v) \(P(PI < 1)\)
4. Decision-tree Approach¶
Problem Checklist¶
- Example 9: Investment outlay with 9 distinct possibilities (shown by decision tree)
Notation¶
- Decision is squared, chance is circled
- Index like so \(D_{11}, D_{22}\) for Decision \(D_{1}\)
At \(D_{1}\), choose \(D_{11}\) and wait for outcome at \(C_{1}\)
Risk & Real Options¶
Types of Option¶
Growth¶
- expand (demand > expectations)
- open new doors, if successful \(\implies\) invest cash
- embedded in capital budgeting projects
Abandonment¶
- abandon/terminate/shutdown prior to its expected economic useful life
- minimize firm's losses
- projects with abandonment value, lower the project's risk by limiting downside losses and improve NPV
- sell off some capacity and put to other use
- variant: suspend (temporarily)
- mineral extractions
- extraction costs > selling price
Timing¶
- optimal time postpone
- accelerate or slow process of implementation
- negative NPV today doesn't mean forever
- traditional contrast, now or never
Flexibility¶
- accept multiple inputs and…
Other Topics¶
PC¶
- Sources and Perspectives on Risk
- Break-even Analysis
- Hillier Model
- Uncorrelated Cash Flows
- Perfectly Correlated Cash Flows
- Simulation Analysis
Limitations Of Sensitivity, Scenario, Simulation & DT Analysis
- Corporate Risk Analysis
- Managing Risk
- Project Selection under Risk3
Ross¶
- Monte Carlo Simulation