Tagging Complex Non-Verbal German Chunks with Conditional Random Fields

We report on chunk tagging methods for German that recognize complex non-verbal phrases using structural chunk tags with Conditional Random Fields (CRFs). This state-of-the-art method for sequence classification achieves 93.5% accuracy on newspaper text. For the same task, a classical trigram tagger approach based on Hidden Markov Models reaches a baseline of 88.1%. CRFs allow for a clean and principled integration of linguistic knowledge such as part-of-speech tags, morphological constraints and lemmas. The structural chunk tags encode phrase structures up to a depth of 3 syntactic nodes. They include complex prenominal and postnominal modifiers that occur frequently in German noun phrases

Tagging Complex Non-Verbal German Chunks with Conditional Random Fields

We report on chunk tagging methods for German that recognize complex non-verbal phrases using structural chunk tags with Conditional Random Fields (CRFs). This state-of-the-art method for sequence classification achieves 93.5% accuracy on newspaper text. For the same task, a classical trigram tagger approach based on Hidden Markov Models reaches a baseline of 88.1%. CRFs allow for a clean and principled integration of linguistic knowledge such as part-of-speech tags, morphological constraints and lemmas. The structural chunk tags encode phrase structures up to a depth of 3 syntactic nodes. They include complex prenominal and postnominal modifiers that occur frequently in German noun phrases

Improved survival in metastatic germ-cell cancer

Background: The prognostic score of the International Germ Cell Cancer Collaborative Group (IGCCCG) in metastatic germ-cell cancers (mGCC) relies on treatments delivered before 1990. It is unclear, if this score is still relevant to contemporary cohorts of patients who receive modern-type chemotherapy and supportive care. Patients and Methods: All patients who underwent cisplatin/etoposide based first-line chemotherapy for mGCC at the University Hospital Zurich (USZ) between 1991 and 2016 were identified retrospectively. Clinical characteristics were extracted from medical charts and patients classified according to the IGCCCG score (J Clin Oncol 1997;15:594). Progression-free survival (PFS) and overall survival (OS) probabilities at 5 years served as outcome parameters. Results: The study cohort consisted of 204 patients at a median age of 32 years and a median follow-up of 4.2 years. According to the IGCCCG score, PFS in the contemporary USZ cohort was 71% overall; 83% for good risk, 69% for intermediate risk and 30% for poor risk patients, p < 0.001. OS for the entire cohort was 88%. In respect to OS, we observed no difference between good risk and intermediate risk patients (94% vs. 91%, p = 0.62), but a statistically significant difference between those two risk groups and poor risk patients, who had an OS of only 65%, p < 0.001. Conclusions: Within the contemporary USZ cohort of mGCC patients no improvements in PFS probabilities were observed compared to the ones predicted by the IGCCCG score for any prognostic category, but marked improvements in OS probabilities for intermediate risk and poor risk patients, possibly due to better salvage treatments