2.5 Risk Measures and Management Strategies
Key Takeaways
- Standard deviation measures total volatility; beta measures sensitivity to the market alone.
- Variance is the square of standard deviation and shares its units problem, which is why standard deviation is quoted.
- Diversification reduces unsystematic risk but cannot remove systematic market risk.
- Correlation below +1 between assets is what makes combining them reduce portfolio volatility.
- Avoidance, mitigation, transfer and retention are the four generic responses to a risk.
Measuring Risk
The syllabus treats risk measurement as the bridge between the conceptual discussion of risk and the practical business of building portfolios. Four measures matter, and each answers a different question.
Standard Deviation — how much do returns bounce around?
Standard deviation measures the dispersion of returns around their average. A scheme with a mean annual return of 12% and a standard deviation of 18% has experienced returns roughly between -6% and +30% in about two years out of three.
It captures total risk — every source of variation, market-driven or company-specific, lumped together. That makes it the right measure when a fund is the investor's whole portfolio, and it is the input to the Sharpe ratio later in the syllabus.
Variance — the same information, less usable
Variance is the average of squared deviations from the mean, and standard deviation is its square root. Because variance is expressed in squared percentage units it cannot be compared to a return, which is why practitioners quote standard deviation. Know the relationship; the exam has asked which is the square of which.
Beta — how much does it move with the market?
Beta measures sensitivity to the market benchmark alone.
| Beta | Interpretation |
|---|---|
| 1.0 | Moves in line with the benchmark |
| Above 1.0 | Amplifies benchmark moves in both directions |
| Below 1.0 | Dampens benchmark moves |
| Near 0 | Largely unrelated to benchmark movement |
A fund with beta 1.25 would be expected to fall about 12.5% when the benchmark falls 10%. Beta captures only systematic risk, so it is meaningful only when the fund is well diversified and the benchmark is genuinely relevant. Beta measured against an unrelated index is a number without meaning — a point examined more than once.
Correlation — do they move together?
Correlation ranges from +1 (perfectly together) through 0 (unrelated) to -1 (perfectly opposite). It is the reason diversification works. Two assets each with 20% volatility, combined equally:
- Correlation +1: portfolio volatility stays at 20%. No benefit.
- Correlation 0: portfolio volatility falls to roughly 14%.
- Correlation -1: the volatilities can offset almost entirely.
Any correlation below +1 delivers some risk reduction, which is why gold earns a place in portfolios on correlation grounds rather than on expected return. Adding four more large-cap equity funds, all correlated near +0.95 to each other, adds names without adding diversification — a distinction investors routinely miss.
Risk Management Strategies
Diversification
Spreading exposure across securities, sectors, issuers and asset classes. It removes unsystematic risk — the company-specific and issuer-specific component — and leaves systematic market risk untouched. Most of the achievable benefit within an asset class arrives with the first twenty to thirty well-chosen holdings; beyond that the curve flattens sharply.
The more powerful diversification is across asset classes, because equity and debt respond to genuinely different drivers. This is the whole basis of asset allocation.
Asset Allocation and Rebalancing
Setting a target mix, then periodically restoring it. If a 60:40 equity-debt portfolio drifts to 72:28 after a strong equity year, rebalancing sells equity and buys debt to return to 60:40. The mechanical effect is that the investor sells what has risen and buys what has lagged, which imposes discipline precisely where emotion pushes the other way.
Risk Transfer — Insurance
Some risks should not be managed inside a portfolio at all. Premature death, disability and major medical expense are transferred to an insurer for a premium. A term life policy and adequate health cover are prerequisites to an investment plan, not competitors with it — without them, one adverse event forces liquidation of every goal-linked investment at the worst moment.
Risk Retention and the Emergency Fund
Small, frequent, affordable risks are retained rather than insured, because insuring them costs more than bearing them. The emergency fund of three to six months' expenses is retention done deliberately: it absorbs job loss or an unbudgeted expense without forcing the sale of long-term holdings.
Horizon Matching and Systematic Investing
Matching each goal's asset mix to its horizon converts volatility from a threat into a tolerable feature. Systematic investing adds a second layer by spreading purchases across time, so the entry price averages out and no single decision date determines the outcome.
The Four Generic Responses
| Response | Meaning | Example |
|---|---|---|
| Avoid | Do not take the exposure | Declining unlisted illiquid instruments entirely |
| Mitigate | Reduce the exposure | Diversifying; shortening duration |
| Transfer | Move it to a third party | Life and health insurance |
| Retain | Accept and fund it yourself | Emergency fund for small shocks |
A competent plan uses all four simultaneously, and the distributor's contribution is knowing which response fits which risk. Insuring against market volatility is not possible; diversifying against premature death is not possible either.
An investor already holds four large-cap equity funds and proposes adding a fifth to "improve diversification". Why is the benefit likely to be small?
A fund has a beta of 0.75 against its benchmark. The benchmark falls by 12%. What movement is expected from the fund on the basis of beta alone?
Which pairing of risk and management response is appropriate?