FRM Part II · FRM Exam Part II · Portfolio Construction
A practitioner complains that mean-variance optimization using sample means yields extreme, concentrated weights. Which feature of Black-Litterman most directly addresses this problem?
Black-Litterman blends equilibrium-implied returns with investor views, so the optimizer starts at a diversified market-weight portfolio and tilts only where views exist. This reduces the extreme, concentrated weights that arise from noisy sample mean estimates.
- AIt forces all weights to be non-negative
- BIt blends equilibrium-implied returns with views, giving a diversified starting point that deviates only where views existCorrect
- CIt eliminates the need for a covariance matrix
- DIt maximizes expected return subject to a tracking error of zero
Explanation
Black-Litterman anchors expected returns to equilibrium, so unconstrained optimization returns market weights absent views and tilts only for assets involved in views. It still needs a covariance matrix and does not impose non-negativity.
Did you get it right without looking?
One question tells you little. A timed set on Portfolio Construction shows your real accuracy, how long you take and where you lose marks.
More Portfolio Construction questions
- Equilibrium excess returns are 4% for Asset X and 6% for Asset Y. A simplified Bayesian update blends a prior mean of 6% for Asset Y (prior …
- An investor combines a value factor portfolio and a momentum factor portfolio. Each has an annual volatility of 10% and an expected excess r…
- A fund is built by a mean-variance optimizer using historical factor return estimates and produces extreme, unstable weights that change gre…
- A fund has volatility of 10% and two managers. Manager 1 has weight 50%, and its marginal contribution to risk (marginal VaR, per unit weigh…
- A fund manager wants a smart beta equity portfolio that harvests the low-volatility factor without large unintended exposures. Which constru…
- Which change to a mean-variance optimization would most directly reduce the extreme, concentrated weights it tends to produce?