Humboldt-Universität zu Berlin | Wirtschaftswissenschaftliche Fakultät | High Dimensional Nonstationary Time Series | About us | News Feed | News 2018 | Dissertation: X. Xu completes PhD Dissertation: X. Xu completes PhD 08.02.2018 Dissertation: X. Xu completes PhD 13.11.2017. Xiu Xu, IRTG PhD student, defended her PhD dissertation on "Hedging with Spectral Risk Measure" with Magna Cum Laude. Congratulations!