Arbeitspapier

The power of (non-)linear shrinking: A review and guide to covariance matrix estimation

Many econometric and data-science applications require a reliable estimate of the covariance matrix, such as Markowitz portfolio selection. When the number of variables is of the same magnitude as the number of observations, this constitutes a difficult estimation problem; the sample covariance matrix certainly will not do. In this paper, we review our work in this area, going back 15+ years. We have promoted various shrinkage estimators, which can be classified into linear and nonlinear. Linear shrinkage is simpler to understand, to derive, and to implement. But nonlinear shrinkage can deliver another level of performance improvement, especially if overlaid with stylized facts such as time-varying co-volatility or factor models.

Language
Englisch

Bibliographic citation
Series: Working Paper ; No. 323

Classification
Wirtschaft
Estimation: General
Financial Econometrics
Portfolio Choice; Investment Decisions
Subject
dynamic conditional correlations
factor models
large-dimensional asymptotics
Markowitz portfolio selection
rotation equivariance

Event
Geistige Schöpfung
(who)
Ledoit, Olivier
Wolf, Michael
Event
Veröffentlichung
(who)
University of Zurich, Department of Economics
(where)
Zurich
(when)
2020

DOI
doi:10.5167/uzh-170642
Handle
Last update
10.03.2025, 11:42 AM CET

Data provider

This object is provided by:
ZBW - Deutsche Zentralbibliothek für Wirtschaftswissenschaften - Leibniz-Informationszentrum Wirtschaft. If you have any questions about the object, please contact the data provider.

Object type

  • Arbeitspapier

Associated

  • Ledoit, Olivier
  • Wolf, Michael
  • University of Zurich, Department of Economics

Time of origin

  • 2020

Other Objects (12)