WSU Lexicon: Portfolio Management

Risk

Risk is exposure to uncertain outcomes, including the possibility of loss. In investing it covers market, credit and liquidity risk as well as non-financial risks such as operational or legal failures. No single statistic captures it; volatility measures one dimension, the spread of returns.

Volatility, the standard deviation of returns, is one measure of risk, not a synonym for it.

The entry

Uncertainty, Not Just Loss

In everyday speech risk means danger. In finance it means uncertainty about outcomes: the chance that the result differs from what was expected, in either direction. An investment with a known, guaranteed payoff carries no risk in this sense even if the payoff is small; an investment with a wide range of possible outcomes is risky even if most of them are gains.

Investors are compensated for bearing some risks and not others. A diversified investor can eliminate company-specific surprises at little cost, so markets do not pay a premium for them. Market-wide risk cannot be diversified away, and assets more exposed to it must offer higher expected returns to attract buyers.

The entry

Many Dimensions, Many Measures

Risk comes in several forms. Market risk stems from swings in interest rates, currencies, commodity prices and asset prices. Credit risk refers to the chance that a borrower or counterparty does not pay in full and on time. Liquidity risk, in the market sense, is the cost of selling quickly, including any price concession. Beyond these financial risks sit non-financial ones: operational failures, legal and regulatory change, model errors and the risk of running out of cash.

Each dimension has its own measures. Standard deviation and beta describe market risk; default probability and loss severity describe credit risk; bid-ask spreads and trading volume describe liquidity. Downside measures such as semideviation, value at risk and maximum drawdown focus on the losses that standard deviation treats symmetrically with gains.

The entry

Why Volatility Is Only Part of the Picture

The standard deviation of returns, called volatility, is the most widely used risk statistic because it is easy to compute and fits neatly into portfolio mathematics. But it treats an unexpected gain exactly like an unexpected loss, and it can understate danger in assets whose returns are skewed or that trade rarely. A private loan valued with a model may show low volatility for years and then lose a large share of its value in a single default.

Variance, the square of standard deviation, is measured in squared units, so it cannot be compared directly with a return expressed in percent. Analysts therefore quote volatility for interpretation and use variance and covariance for calculation.

The entry

What Candidates Need to Show

Candidates should distinguish total risk from systematic risk, explain why only systematic risk is priced in the CAPM, and know which measure fits which question: standard deviation for the total risk of a portfolio, beta for an asset's contribution to a diversified portfolio, and downside measures when losses matter more than symmetric variation. In risk management, they should be able to place a given risk in the financial or the non-financial group.

The broader discipline is to name the risk before measuring it. A question about default, illiquidity or a legal dispute is not answered by quoting a standard deviation, and a low volatility figure is no evidence that an investment is safe.

Common trap

“Risk and volatility mean the same thing.”

Volatility measures how widely returns spread around their mean, up and down alike. Risk is broader: default, illiquidity, leverage and operational failures can cause losses in assets whose measured volatility looked low until the moment it mattered.

In practice

Silicon Valley Bank, March 2023

Silicon Valley Bank failed in March 2023 while holding large amounts of high-quality government and agency securities. The losses came from interest rate risk on long-dated holdings and a rapid run on deposits, not from borrowers defaulting.

Candidates ask

Questions on this term

Is risk the same as the chance of losing money?Not quite. In finance, risk is uncertainty about outcomes, so results better than expected are part of it too. Investors care most about the downside, which is why value at risk and drawdown sit alongside standard deviation.
What is the difference between systematic and unsystematic risk?Systematic risk comes from market-wide forces, such as recessions or interest rate changes, and affects most assets together, so diversification cannot remove it. Unsystematic risk is specific to a company or industry, such as a failed product launch, and largely disappears in a well-diversified portfolio. In the CAPM only systematic risk, measured by beta, earns a risk premium.
How do organizations classify the risks they face?A common split separates financial risks, which arise from markets and counterparties (market risk, credit risk and liquidity risk), from non-financial risks, which arise from the organization itself or its environment (operational, legal, regulatory, model, tax and settlement risk, among others). The categories interact: an operational failure can trigger a funding problem that becomes a credit event.

Related entries

Standard DeviationStandard deviation is the square root of variance: a measure of how widely observations disperse around their mean, expressed in the same units as the data.
Systematic RiskSystematic risk is the portion of an asset's total risk that stems from economy-wide factors (interest rates, inflation, growth shocks, geopolitics) and therefore cannot be removed by diversification.
Value at RiskValue at Risk (VaR) is the minimum loss expected on a portfolio over a specified period at a specified probability level.
VolatilityVolatility is the standard deviation of an asset's returns, usually stated on an annual basis.

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Risk

Volatility, the standard deviation of returns, is one measure of risk, not a synonym for it.