Skip to content

FRM Part I · FRM Exam Part I · The Black-Scholes-Merton Model

A stock follows geometric Brownian motion with expected return μ = 11% per year and volatility σ = 20% per year. What is the expected continuously compounded (log) return per year, ln(S_T/S_0)/T in expectation?

The expected continuously compounded return equals the drift minus half the variance: 11% − 0.5 × (0.20)² = 11% − 2% = 9% per year. Using 11% ignores the Ito adjustment that arises because the price is lognormal.

  1. A11%
  2. B9%Correct
  3. C13%
  4. D10%

Explanation

The expected log return is μ − σ²/2 = 0.11 − 0.04/2 = 0.11 − 0.02 = 0.09, or 9%. Using 11% ignores the Ito convexity adjustment. Adding the adjustment (13%) has the wrong sign.

Did you get it right without looking?

One question tells you little. A timed set on The Black-Scholes-Merton Model shows your real accuracy, how long you take and where you lose marks.

More The Black-Scholes-Merton Model questions