Sharpe Ratio Mental Math Interview Guide
Sharpe ratio mental math interview guide for rough return-over-volatility arithmetic, annualization caveats, and interpretation.
Candidates preparing for risk-adjusted return discussions.
Sharpe is return per unit risk
At a high level, a Sharpe-style ratio compares excess return with volatility. In interviews, focus on the interpretation and assumptions.
Do the rough division
If excess return is 8 and volatility is 16 in matching units, the ratio is 0.5. Matching the time horizon matters before dividing.
Concrete example
A strategy with 12 percent excess return and 6 percent volatility has a rough ratio of 2 under the simplified arithmetic.
Mention caveats
Sharpe-style summaries can hide tails, skew, costs, and instability. Use the ratio as a summary, not a guarantee of future performance or risk control.
Common mistakes
Candidates often divide numbers from different horizons or treat a higher ratio as risk-free. Risk-adjusted is not riskless.
Practice the pattern
Use the LeetQuidity curriculum and calibration to turn this topic into a focused practice plan.