Research brief 009

11.17% versus 14.08% volatility. Can missing histories improve the risk question?

A neural estimator uses unequal stock histories without discarding the longer records. The authors report a sizeable risk difference.

The idea worth investigating

A recently listed stock should not erase years of observations for the rest of a portfolio. Bongiorno and Villassero build a covariance estimator around incomplete histories and train it on realized portfolio risk.

The full analysis examines the study and the practical question behind it: A neural estimator uses unequal stock histories without discarding the longer records. The authors report a sizeable risk difference.

Paper-based analysis; no independent house test has been completed.

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See what changes the investment case.

The headline is the starting point. The subscriber analysis takes you through:

  • The estimator and its comparison set
  • Return, drawdown and cost evidence
  • The replication controls we would require
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