Ludwig-Maximilians-Universität München
Open Access LMU ( Ludwig-Maximilians-Univ. München)Not a member yet
40914 research outputs found
Sort by
Das Bürokratische Zeitalter – Ursachen von Gesetzeskosten und ihre Auswirkung auf die Standortqualität
Get PDF
Resection of a singular metachronous testicular metastasis of prostate cancer: A case report
Get PDFWe present the case of a 66-year-old patient with a biochemical recurrence of prostate cancer manifesting as an asymptomatic testicular metastasis. Two years after radical prostatectomy and salvage radiation, the prostate-specific antigen (PSA) level rose to 1.07ng/ml. PSMA PET/CT scan showed tracer accumulation in the left testicle. Inguinal orchiectomy confirmed the metastasis. After being non-detectable, the PSA level increased five months after orchiectomy, with PSMA PET/CT revealing positive iliac lymph nodes. In summary, the presented case illustrates orchiectomy as a metastasectomy. However, apart from a transient decrease in PSA, no medium-term oncological advantage could be seen
Aleatoric and Epistemic Uncertainty in Conformal Prediction
Get PDFRecently, there has been a particular interest in distinguishing different types of uncertainty in supervised machine learning (ML) settings (Hullermeier and Waegeman, 2021). Aleatoric uncertainty captures the inherent randomness in the data-generating process. As it represents variability that cannot be reduced even with more data, it is often referred to as irreducible uncertainty. In contrast, epistemic uncertainty arises from a lack of knowledge about the underlying data-generating process, which–in principle–can be reduced by acquiring additional data or improving the model itself (viz. reducible uncertainty). In parallel, interest in conformal prediction (CP)–both its theory and applications–has become equally vigorous. Conformal Prediction (Vovk et al., 2005) is a model-agnostic framework for uncertainty quantification that provides prediction sets or intervals with rigorous statistical coverage guarantees. Notably, CP is distribution-free and makes only the mild assumption of exchangeability. Under this assumption, it yields prediction intervals that contain the true label with a user-specified probability. Thus, CP is seen as a promising tool to quantify uncertainty. But how is it related to aleatoric and epistemic uncertainty? In particular, we first analyze how (estimates of) aleatoric and epistemic uncertainty enter into the construction of vanilla CP–that is, how noise and model error jointly shape the global threshold. We then review “uncertainty-aware” extensions that integrate these uncertainty estimates into the CP pipeline
Random forest calibration
Get PDFThe Random Forest (RF) classifier is often claimed to be relatively well calibrated when compared with other machine learning methods. Moreover, the existing literature suggests that traditional calibration methods, such as isotonic regression, do not substantially enhance the calibration of RF probability estimates unless supplied with extensive calibration data sets, which can represent a significant obstacle in cases of limited data availability. Nevertheless, there seems to be no comprehensive study validating such claims and systematically comparing state-of-the-art calibration methods specifically for RF. To close this gap, we investigate a broad spectrum of calibration methods tailored to or at least applicable to RF, ranging from simple scaling techniques to more advanced algorithms. Our results based on synthetic as well as real-world data unravel the intricacies of RF probability estimates, scrutinize the impact of hyper-parameters, and compare calibration methods in a systematic way. We demonstrate that a well-optimized RF matches or outperforms state-of-the-art calibration methods. In particular, statistical tests on metrics such as accuracy, ECE, Brier score, and log-loss consistently place the optimized RF among the top-performing group
The Affective Gap in Economic Grievance Based Explanations of Right-Wing Populist Voting: A Literature Review
Get PDFSinging History: Politics of Idiom and Genre in Ted Hearne’s Music(al)-Theatre
Get PDFIn his productions, The Source (2014) and over and over vorbei nicht vorbei (2024), composer Ted Hearne deals with explicitly historio-political subjects and the memories of violent past(s). The pieces explore questions of documentation and representation, the authentic and the ‘fake’, the virtual and the real. This article examines how Hearne and his collaborators deconstruct political content, how they (re-)arrange, compose, and stage it using an eclectic mix of styles, employing various vocal characteristics, and staging words, video, and music in unconventional arrangements. Their productions thus foster empathetic acts of witnessing (see Kopf 2009), which I suggest to be a key characteristic of Hearne’s works
Ba2BP7N14 : A Quaternary Alkaline Earth Nitridoborophosphate with a Mixed 3D Network Structure
Get PDFHighly condensed alkaline earth nitridophosphates have attracted increasing scientific interest, due to their high thermal and chemical stability, as well as their promising luminescence behavior upon doping with Eu2+ for pc-LED applications. In particular, the barely explored mixed tetrahedra-based nitridophosphates offer a wide range of structural and compositional diversity, enabling new insights into structure-property relationships. Herein, we report on the first quaternary alkaline earth nitridoborophosphate Ba2BP7N14, synthesized at 8 GPa and 1600 °C in a multianvil press, starting from Ba(N3)2, h-BN and P3N5. Ba2BP7N14 crystallizes in the barylite-1O polytype and features a highly condensed mixed (B,P)–N anionic 3D network (κ≈0.57) built up of PN4 and mixed occupied (P0.75B0.25)N4 tetrahedra. The structure was characterized by a multi-step process involving single-crystal and powder X-ray diffraction (SCXRD, PXRD), elemental analysis, electron microscopy (STEM, EELS), and solid-state 31P and 11B MAS NMR spectroscopy. The plausibility of the structural model was corroborated by low-cost crystallographic calculations. The optical band gap and the thermal behavior of an undoped sample of Ba2BP7N14, were determined from diffuse reflectance spectroscopy and temperature-dependent powder X-ray diffraction, respectively. Irradiation of a Eu2+-doped sample with near-UV light results in a blue emission peaking at λem=422 nm