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Expert finding in the legal community seeks to identify lawyers with the correct expertise to answer ordinary citizens questions. The knowledge disparity between citizens and lawyers is high. In this paper we seek to reproduce the findings of Askari et al. research on a legal Q&A forums data combining multiple ranking methods.

The present thesis addresses both theoretical as well as numerical aspects of the treatment of nonlinear inverse problems. The first part considers Tikhonov regularization for nonlinear ill-posed operator equations in Hilbert scales with oversmoothing penalties. Sufficient as well as necessary conditions to establish convergence are introduced and convergence rate results are given for various parameter choice rules under a two sided nonlinearity constraint. Ultimately, both a posteriori as well as certain a priori parameter choice rules lead to identical converce rates. The theoretical results are supported and augmented by extensive numerical case studies. In particular it is shown, that the localization of the above mentioned nonlinearity constraint is not trivial. Incorrect localization will prevent convergence of the regularized to the exact solution. The second part of the thesis considers two open problems in inverse option pricing and electrical impedance tomography. While regularization through discretization is sufficient to overcome ill-posedness of the latter, the first requires a more sophisticated approach. It is shown, that the recovery of time dependent volatility and interest rate functions from observed option prices is everywhere locally ill-posed. This motivates Tikhonov-type or variational regularization with two parameters and penalty terms to simultaneously recover these functions. Two parameter choice rules using the L-hypersurface as well as a combination of L-curve and quasi-optimality are introduced. The results are again supported by extensive numerical case studies.

This paper investigates a specific ill-posed nonlinear inverse problem that arises in financial markets. Precisely, as a benchmark problem in the context of volatility surface calibration, we consider the simultaneous recovery of implied volatility and interest rate functions over a finite time interval from corresponding call- and put-price functions for idealized continuous families of European vanilla options over the same maturity interval. We prove identifiability of the pair of functions to be identified by showing injectivity of the forward operator in L2-spaces. To overcome the ill-posedness we employ a two-parameter Tikhonov regularization with heuristic parameter choice rules and demonstrate chances and limitations by means of numerical case studies using synthetic data.

The automotive industry is in the midst of historic change: changing consumer preferences, new technologies and tougher sustainability requirements. Car manufacturers are forced to transform their businesses fundamentally while striking a balance between current needs and future opportunities. In recent years, collaborative product development has become an important business strategy as a means to respond to the changing market conditions. Despite many benefits, however, collaborations with suppliers place substantial pressure on the focal firm as joint efforts must be managed and coordinated carefully. The purpose of this thesis was to explore the feasibility of outsourcing coordination of supplier involvement in collaborative product development projects. The purpose was operationalized by a research question seeking to identify characteristic risk factors in the aforementioned outsourcing context. Thus, the thesis was built upon a theoretical foundation of the interface between collaborative product development, outsourcing and risk management theories. In the methodology, a multi-step research design was taken that included reviewing documents, observing participants as well as conducting interviews and workshops. The analysis yielded a comprehensive overview of relevant risk factors in outsourcing coordination of supplier involvement in collaborative product development projects. The outsourcing practice has proven to be inherently risky as a total of 10 different risk factors were identified and their characteristics assessed. The research has shown that both effective risk management strategies and adjustment to corporate regulations and policies are required if the outsourcing practice is to be implemented within the contextual setting studied in the thesis. The research findings have further contributed to the existing body of literature on relevant outsourcing risk factors. Bilindustrin är mitt i en historisk förändring: förändrade kundpreferenser, nya teknologier och hårdare krav på hållbarhet. Biltillverkare är tvingade till fundamentala förändringar av deras företag samtidigt som de måste hålla en balans mellan nuvarande behov och framtida möjligheter. Under senare år har kollaborativ produktutveckling blivit en viktig affärsstrategi för att svara på föränderliga marknadsförhållanden. Trots många fördelar skapar kollaborationer med leverantörer betydande tryck på fokalföretaget där alla förenade insatser måste ledas och koordineras försiktigt. Syftet med avhandlingen var att utforska möjligheten att outsourca koordinering av leverantörsinblandning i kollaborativa produktutvecklingsprojekt. Syftet blev operationaliserat av en forskningsfråga som sökte att identifiera karaktäristiska riskfaktorer i den tidigare nämnda outsourcing kontexten. Således var avhandlingen byggd på en teoretisk grund av gränssnittet mellan kollaborativ produktutveckling, outsourcing och riskhanteringsteorier. I metoden togs en flerstegad forskningsdesign som inkluderade att granska dokument, observera deltagare samt utföra intervjuer och workshops. Analysen gav en omfattande översikt av relevanta riskfaktorer i outsourcing av koordinering av leverantörsinblandning i kollaborativa produktutvecklingsprojekt. Bruket av outsourcing har bevisats att innebära risker, totalt 10 olika riskfaktorer blev identifierade och deras karaktäristik bedömdes. Forskningen har visat att både effektiva riskhanteringsstrategier och justering av företagsbestämmelser behövs om bruket av outsourcing ska kunna implementeras inom den kontext som studerades inom avhandlingen. Fynden i forskningen har bidragit till den existerande litteraturen om riskfaktorer i outsourcing

Elaborate visual signals, such as intense, highly-contrasting colors, have intrigued biologists for centuries. Although many intraspecific studies have investigated the function and evolution of elaborate coloration, comprehensive, detailed, interspecific studies of color are rare. To better understand the evolution of elaborate coloration, we measured New World oriole plumage using a reflectance spectrometer. We then used these color measurements to reconstruct evolutionary changes in male and female coloration across the oriole phylogeny. ; We found that adult male oriole coloration is produced by two different pigment classes, carotenoids and phaeomelanins. In at least one taxon having phaeomelanin-based coloration, carotenoids were still present in large enough quantities to produce color, indicating that phaeomelanins were masking carotenoid coloration. Ancestral state reconstruction suggested that orioles with phaeomelanin-based colors arose from an ancestor with carotenoid coloration, indicating that the directionality of the pigment change was from carotenoid to phaeomelanin. These changes appear to have occurred multiple times; however, all changes are found within only one of the three major oriole lineages. When we focused on male carotenoid-based colors, we found continuous variation from yellow to scarlet. Ancestral state reconstruction of spectral location suggested that carotenoid coloration was labile, with several large color changes occurring among closely related orioles. Although coloration was labile, related taxa resembled each other greater than expected due to chance, suggesting that a significant amount of phylogenetic signal was present. However, the strength of this signal was weak and it did not appear to limit color evolution. Although male orioles varied considerably in their spectral location, they varied little in their degree of elaboration. All males had a highly-contrasting appearance, with saturated color plumage, and dark, melanin-based, achromatic plumage. In contrast, females varied considerably in carotenoid saturation and the brightness of their melanin-based plumage. Comparative analyses suggested that these changes in female saturation and melanin brightness were correlated. Finally, we studied the evolution of sexual dichromatism in a phylogenetic context. Ancestral state reconstruction suggested that females repeatedly lost elaborate coloration, which led to multiple gains of sexual dichromatism. These findings differ from the traditional paradigm of increased male elaboration leading to sexual dichromatism.