Sökning: "Smooth Splines"

Visar resultat 1 - 5 av 8 avhandlingar innehållade orden Smooth Splines.

1. 1. Economic Implications of Corporate Social Responsibility and Responsible Investments

   Författare :Cristiana Manescu; Göteborgs universitet; []
   Nyckelord :SAMHÄLLSVETENSKAP; SOCIAL SCIENCES; Corporate Social Responsibility; Strategic CSR; Socially Responsible Investments; Sustainability; Firm Profitability; Stock Returns; Statistical Learning Techniques; Variable Selection; Smooth Splines; Regression Trees; Data Envelopment Analysis; Difference-GMM; Risk-Factor Test; Market Efficiency; Control Functions Approach.;

   Sammanfattning : Paper 1 (with Catalin Starica): This study conducts an in-depth analysis of the association between a unique ten-dimensional set of Corporate Social Responsibility (CSR) scores and firm profitability, as measured by Return on Assets (ROA). We find that non-linear (semi or non-parametric) regression methods bring important improvements in explaining profitability relative to a classical linear approach. LÄS MER

3. 2. Computer Aided Angioplasty : Patient-specific arterial modeling and smooth 3D contact analysis of the stent-balloon-artery interaction

   Författare :Dimitrios Kiousis; Gerhard Holzapfel; Kenneth Runesson; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Contact; continuous surfaces; B-splines; balloon angioplasty; stenting; FEM; Bioengineering; Bioteknik;

   Sammanfattning : Paper A: In this paper, the development and implementation of a contact algorithm based on C2-continuous surface representations is discussed. In 3D contact simulations involving models with arbitrarily curved surfaces (as in the case of vessel walls), the discretization of the contact surfaces by means of facet-based techniques could lead to numerical instabilities and finally loss of quadratic convergence. LÄS MER

4. 3. Bayesian Modeling of Conditional Densities

   Författare :Feng Li; Mattias Villani; Sylvia Frühwirth-Schnatter; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Bayesian inference; Density estimation; smooth mixtures; surface regression; copulas; Markov chain Monte Carlo; Statistics; statistik;

   Sammanfattning : This thesis develops models and associated Bayesian inference methods for flexible univariate and multivariate conditional density estimation. The models are flexible in the sense that they can capture widely differing shapes of the data. The estimation methods are specifically designed to achieve flexibility while still avoiding overfitting. LÄS MER

5. 4. Trajectory Tracking and Prediction-Based Coordination of Underactuated Unmanned Vehicles

   Författare :Dzenan Lapandic; Bo Wahlberg; Antonio Pedro Aguiar; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Electrical Engineering; Elektro- och systemteknik;

   Sammanfattning : In this thesis, we study trajectory tracking and prediction-based control of underactuated unmanned aerial and surface vehicles.  In the first part of the thesis, we examine the trajectory tracking using prescribed performance control (PPC) assuming that the model parameters are unknown. LÄS MER

7. 5. Generalized survival models as a tool for medical research

   Författare :Xingrong Liu; Karolinska Institutet; Karolinska Institutet; []
   Nyckelord :;

   Sammanfattning : In medical research, many studies with the time-to-event outcomes investigate the effect of an exposure (or treatment) on patients’ survival. For the analysis of time-to-event or survival data, model-based approaches have been commonly applied. LÄS MER