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Brief CV

• Since 03/2019: Postdoctoral Researcher at the Faculty of Statistics, Technical University of Dortmund.

• 04/2018-02/2019: Postdoctoral Researcher at the Institute of Statistics, University of Ulm.

• 06/2017 - Graduation Dr. rer. nat.,  Mathematical Institute, University of Duesseldorf. Title of PhD thesis: The power of tests for signal detection in high-dimensional data.

• 04/2014-03/2018: Research assistent at the Mathematical Institute, University of Duesseldorf.

• 10/2012 - 03/2014: Studies of Mathematics (M.Sc.) at the University of Duesseldorf. Title of Master thesis: Tests auf proportionale Hazards für zensierte Daten (translation: Tests for proportional hazards under censored data).

• 10/2009 - 09/2012: Studies of Mathematics and Applications (B.Sc.) at the University of Duesseldorf. Title of Bachelor thesis: Der lokale zentrale Grenzwertsatz (translation: The local central limit theorem).

  
  

   

Research Interests

• Inference in Survival Analysis
• Solutions for the problem of non-proportional hazards and crossing survival curves
• Methods for general, heterogeneous factorial designs
• Resampling techniques (especially Permutation methods) for small sample sizes
• Functional and high-dimensional data

Projects

• Modellierung und Quantifizierung von Effektgrößen für faktorielle Daten in der Überlebenszeitanalyse (German Research Foundation Grant No PA 2409/5-1)

R-Packages

• mdir.logrank: available on CRAN. This packages contains the flexible combination approach of weighted log-rank-test for the two-sided (Ditzhaus and Friedrich, 2020) and the one-sided problem (Ditzhaus and Pauly, 2019)
• GFDsurv: avaibable on CRAN. This packages contains three different tests for survival data in general factorial designs (Ditzhaus, Dobler and Pauly, 2021; Ditzhaus, Janssen and Pauly, 2020; Dobler and Pauly, SMMR, 2019).

Preprints

1. Dormuth, Liu, Xu, Pauly, Ditzhaus (2021). Testing for difference in survival in non-standard situations. In final preparation.
2. Ditzhaus, Yu and Xu (2021). Studentized Permutation Method for Comparing Restricted Mean Survival Times with Small Sample from Randomized Trials. (arXiv:2102.10186).
3. Ditzhaus and Janssen (2019). Dependence correction of multiple tests with applications to sparsity. (arxiv:1909.13727)

Publications

2022

• Ditzhaus and Gaigall.  Testing marginal homogeneity in Hilbert spaces with applications to stock market returns. TEST, doi: 10.1007/s11749-022-00802-5.
• Dormuth, Liu, Xu, Yu, Pauly, Ditzhaus. Which Test for Crossing Survival Curves? A Systematic Review.  BMC Medical Research Methodology (published online, open access).
• Ditzhaus and Smaga. Permutation test for the multivariate coefficient of variation in factorial designs. Journal of Multivariate Analysis, Vol. 187, 104848.

2021

• Guckel, Niemann, Ditzhaus, Molatta, Bergau, Fink, Sciacca, El Hamriti, Imnadze, Steinhauer, Braun, Khalaph, Nölker, Sommer, Sohns. Long-term efficacy and impact on Mortality of Remote Magnetic Navigation guided catheter ablation of Ventricular Arrhythmias. Journal of Clinical Medicine, Vol. 10, 4695.
  

• Ditzhaus, Genuneit, Janssen, Pauly. CASANOVA: Permutation inference in factorial survival designs. Biometrics, early View.
• Lin, Vitkova, Asseyer, Serra, Motamedi, Chien, Ditzhaus, Papadopoulou, Benkert, Kuhle, Bellmann-Strobl, Ruprecht, Paul, Brandt, and Zimmermann. Increased serum neurofilament light and thin ganglion cell-inner plexiform layer are additive risk factors for disease activity in early MS. Neurology: Neuroimmunology & Neuroinflammation, Vol. 8, e1051.
• Ditzhaus, Fried and Pauly. QANOVA: Quantile-based Permutation Methods For General Factorial Designs. TEST (published online).
• Ditzhaus, Dobler, Pauly. Inferring median survival differences in general factorial designs via permutation tests. Statistical Methods in Medical Research, Vol. 30, 875-891.

2020

• Fernandez, Xu, Ditzhaus and Gretton. A kernel test for quasi-independence. Advances in Neural Information Processing Systems 33.
  

• Ditzhaus and Friedrich. More powerful logrank permutation tests for two-sample survival data. Journal of Statistical Computation and Simulation, Vol. 90, 2209-2227.
  
• Liu*, Ditzhaus* and Xu. A resampling-based test for two crossing survival curves. Pharmaceutical Statistics, Vol. 19, 399-409 (*equal contribution).

• Ditzhaus and Janssen. Bootstrap and permutation rank tests for proportional hazards under right censoring. Lifetime Data Analysis, Vol. 26, 493-517.

2019

• Ditzhaus. Signal detection via Phi-divergences for general mixtures. Bernoulli, Vol. 25, No 4A, 3041-3068.
• Ditzhaus and Pauly. Wild bootstrap logrank tests with broader power functions for testing superiority. Computational Statistics and Data Analysis, Vol.134, 1-11. 
• Ditzhaus and Janssen. Variability and stability of the false discovery proportion. Electronic Journal of Statistics, Vol. 13, 882-910.

2018

• Ditzhaus and Janssen. Detectability of nonparametric signals: higher criticism versus likelihood ratio. Electronic Journal of Statistics, Vol.12, 4094-4137. 
• Ditzhaus and Gaigall. A consistent goodness-of-fit test in separable Hilbert spaces. Journal of Nonparametric Statistics, Vol. 30, No. 4, 834-859. 

Teaching

• Seminar "Empirical processes" (Winter 2021/22)

• Lecture "Statistical Methods" (Winter 2021/22)
• Intensive course in Statistic (Summer 2021)
• Exercise for Decision Theory  (Summer 2021)
• Seminar "Survival Analysis" (Summer 2020)

Supervised Thesis

• Random survival forests beyond the Cox model: Simulation study for new splitting rules (Bachelor thesis, 2021)
• Quantile-based MANOVA: A new tool for inferring multivariate data in factorial designs. (Master thesis, 2021)
• Solutions for the curse of non-proportional hazards: The potential of the net benefit in clinical trials (Bachelor thesis, 2021)
• Analysing the Development of IQ in a South African Sample from Childhood to Emerging Adulthood using Latent Class Mixed Models (Bachelor thesis, 2020). This thesis was award by the Alumni Association as the best bachelor thesis.

Grants and Awards

• Minerva Short-Term Research Grant for Isreal (2020)
• Joachim Hartung Prize, Young Researcher Award, International Workshop of the DR-IBS WG Nonparametric Methods (2020)
• DAAD-Grant Vortragsreisenprogramm for New Zealand (2017)
• HeRA-Grant (Heine Research Acadamies) for New Zealand (2017)

Miscellaneous

• Member of the International Biometric Society (IBS-DR)