An Event Study Into Dividend Payments and Possible Profitable Trading Strategies, in the Norwegian Stock Market

Master's thesis in Applied Finance.This Thesis contains a detailed event analysis where market efficiency in the event of dividend pay-outs in the Norwegian stock market is analysed. The event analysis uses two introduced main hypothesis’ in the form of trading strategies to establish whether either can obtain abnormal returns. This is, excess return beyond the normal return that is to be expected based on the stocks previous correlation to the market movements. Hypothesis 1, the dividend inclusive strategy targets the period between the dividend announcement and the ex-dividend date. This follows from the assumption that abnormal stock price movements happen after the announcement of dividend, and that investor preferences might influence the efficiency of the stock price in this period. Hypothesis 2, the ex-dividend strategy targets the period after the ex-dividend date. The hypothesis is that stocks is inefficient after the ex-dividend date due to investor preferences and that the stock price returns to efficiency after an unknown time period. The ending date for the ex-dividend strategy is calculated using the risk adjusted return of the stocks in the sample. The optimal ending time is calculated to be nine days after the ex-dividend date as it has the highest cumulative abnormal return. The analysis shows that both individual trading strategies as well as both collectively has positive cumulative average abnormal returns. However, the CAAR’s are small and paired with the respective standard deviations, the significance tests reveal that they are not significant at a meaningful level of confidence. Although the abnormal returns for the trading strategies were not significant, the event study give additional support to existing theories such as the market efficiency theory (1970) and dividend irrelevancy (Miller & Modigliani, 1961). The data material also revealed elevated volatility in the days following the ex-dividend date. This justifies a strong encouragement for future research to establish the cause and implications of such. Finally, the recent introduction of new taxation arrangement concerning private investors in Norway might change investors preferences concerning dividend going forward. This is also an important subject for future research in the field when sufficient data becomes available

Design of a Simulated Hospital Tour in a Scanned 3D Model for Children

Master's Thesis in Joint Master's Programme in Software Engineering - collaboration with HVLPROG399MAMN-PRO

State of the art and challenges in sequence based T-cell epitope prediction

Sequence based T-cell epitope predictions have improved immensely in the last decade. From predictions of peptide binding to major histocompatibility complex molecules with moderate accuracy, limited allele coverage, and no good estimates of the other events in the antigen-processing pathway, the field has evolved significantly. Methods have now been developed that produce highly accurate binding predictions for many alleles and integrate both proteasomal cleavage and transport events. Moreover have so-called pan-specific methods been developed, which allow for prediction of peptide binding to MHC alleles characterized by limited or no peptide binding data. Most of the developed methods are publicly available, and have proven to be very useful as a shortcut in epitope discovery. Here, we will go through some of the history of sequence-based predictions of helper as well as cytotoxic T cell epitopes. We will focus on some of the most accurate methods and their basic background

CPHmodels-3.0--remote homology modeling using structure-guided sequence profiles

CPHmodels-3.0 is a web server predicting protein 3D structure by use of single template homology modeling. The server employs a hybrid of the scoring functions of CPHmodels-2.0 and a novel remote homology-modeling algorithm. A query sequence is first attempted modeled using the fast CPHmodels-2.0 profile-profile scoring function suitable for close homology modeling. The new computational costly remote homology-modeling algorithm is only engaged provided that no suitable PDB template is identified in the initial search. CPHmodels-3.0 was benchmarked in the CASP8 competition and produced models for 94% of the targets (117 out of 128), 74% were predicted as high reliability models (87 out of 117). These achieved an average RMSD of 4.6 A when superimposed to the 3D structure. The remaining 26% low reliably models (30 out of 117) could superimpose to the true 3D structure with an average RMSD of 9.3 A. These performance values place the CPHmodels-3.0 method in the group of high performing 3D prediction tools. Beside its accuracy, one of the important features of the method is its speed. For most queries, the response time of the server i

High-Pressure Diffraction Studies of Rubidium Phase IV

Rb-IV is the stable high-pressure phase of rubidium between 16 and 21 GPa. The structure of Rb-IV has long been known to be complex, but it is only recently that it has been solved as being an incommensurate host-guest composite structure, comprising a tetragonal host framework containing chains of "guest" atoms that form structures incommensurate with the host along their common c- axis. While similar composite structures have been observed in a number of other elemental metals, Rb-IV is unique in that on pressure decrease below 16.7 GPa at 300 K, the chains of guest atoms become disordered and liquid-like. This thesis is a detailed structural study of Rb-IV. High-pressure, combined with high-temperature powder diffraction techniques, have been used to map the P-T phase diagram of rubidium between 15 GPa and 20 GPa and between 298 K and 600 K. The results show that the guest order-disorder transition pressure is strongly temperature dependent, and that the disordered phase is observed to the highest temperatures. Technical developments, which have made it possible to extract reliable modulation reflection intensities from a Rb-IV single crystal, are described. The resulting data are used for a full modulated structure refinement of Rb-IV, revealing a saw-tooth shaped modulation of the guest structure, from which new information on the host-guest interactions has been extracted. Inelastic X-ray scattering techniques have been used to measure the longitudinal acoustic (LA) phonons in a Rb-IV single crystal. Two LA-like phonon branches, one for each of the two composite subsystems, are observed along the common c-axis. The sound velocities in the host and guest structures are determined and the pressure dependence is shown to differ by a factor of two. Finally, developments that will enable future combined high-pressure high- temperature single-crystal diffraction studies, and single-crystal diffraction studies at pressures above 100 GPa, will be presented

Chemical genetics in zebrafish: modulation of cAMP and MAPK pathways in behaviour

The prevalence of stress and anxiety disorders in modern society is increasing, but the development of new treatments decreasing due to high research costs and low success rates in clinical trials. The latest type of compounds introduced to treat anxiety and depression was the specific serotonin reuptake inhibitors (SSRI), which was introduced in 1987. Since then, no new class of compounds have been introduced, suggesting that the need to find alternative targets in treating mental disorders is needed. In this thesis I have used the zebrafish as a model organism to study the modulation of behaviours through intracellular signalling pathways, known to be involved in learning, memory and anxiety. First, using the pro-convulsant compound, pentylenetetrazole (PTZ), an automated tracking system was established to quantify and analyse swimming behaviour in larvae zebrafish. Pentylenetetrazole induces seizures in zebrafish at high concentrations, however this thesis identifies that the combination of a low level of PTZ and subjecting the fish to alternating cycles of light and dark induced a reversed response to light and dark. A group of compounds with known anti-seizure effects were subsequently screened, which found that a combinational treatment with diazepam and two types of neurosteroids reversed the PTZ-induced light dark response. Secondly, using the same automated analysis setup, the effect of cAMP modulators was studied on behaviour in zebrafish larvae. Our lab has previously established that Rolipram, a PDE4 inhibitor, causes anxiety thigmotaxis in zebrafish larvae. In this thesis we treated zebrafish larvae with Rolipram and other compounds modulating cAMP, which greatly increased the swimming activity, which was reversed by subsequently treating with PD0325901. To test if the pharmacological modulation of cAMP-levels through the inhibition of other PDEs would lead to increased locomotor activity, a small library of PDE inhibitors was screened, and 4 compounds were identified that caused an increase in locomotion – three of these compounds were PDE4-inhibitors. Finally, by using two behavioural assays, I found that in adult fish Rolipram cause anxiety-like phenotypes, which is also reversible by MAPK-inhibition

A generic method for assignment of reliability scores applied to solvent accessibility predictions

<p>Abstract</p> <p>Background</p> <p>Estimation of the reliability of specific real value predictions is nontrivial and the efficacy of this is often questionable. It is important to know if you can trust a given prediction and therefore the best methods associate a prediction with a reliability score or index. For discrete qualitative predictions, the reliability is conventionally estimated as the difference between output scores of selected classes. Such an approach is not feasible for methods that predict a biological feature as a single real value rather than a classification. As a solution to this challenge, we have implemented a method that predicts the relative surface accessibility of an amino acid and simultaneously predicts the reliability for each prediction, in the form of a Z-score.</p> <p>Results</p> <p>An ensemble of artificial neural networks has been trained on a set of experimentally solved protein structures to predict the relative exposure of the amino acids. The method assigns a reliability score to each surface accessibility prediction as an inherent part of the training process. This is in contrast to the most commonly used procedures where reliabilities are obtained by post-processing the output.</p> <p>Conclusion</p> <p>The performance of the neural networks was evaluated on a commonly used set of sequences known as the CB513 set. An overall Pearson's correlation coefficient of 0.72 was obtained, which is comparable to the performance of the currently best public available method, Real-SPINE. Both methods associate a reliability score with the individual predictions. However, our implementation of reliability scores in the form of a Z-score is shown to be the more informative measure for discriminating good predictions from bad ones in the entire range from completely buried to fully exposed amino acids. This is evident when comparing the Pearson's correlation coefficient for the upper 20% of predictions sorted according to reliability. For this subset, values of 0.79 and 0.74 are obtained using our and the compared method, respectively. This tendency is true for any selected subset.</p

Spiral Chain O4 Form of Dense Oxygen

Oxygen is in many ways a unique element: the only known diatomic molecular magnet and the capability of stabilization of the hitherto unexpected O8 cluster structure in its solid form at high pressure. Molecular dissociations upon compression as one of the fundamental problems were reported for other diatomic solids (e.g., H2, I2, Br2, and N2), but it remains elusive for solid oxygen, making oxygen an intractable system. We here report the theoretical prediction on the dissociation of molecular oxygen into a polymeric spiral chain O4 structure (\theta-O4) by using first-principles calypso method on crystal structure prediction. The \theta-O4 stabilizes above 2 TPa and has been observed as the third high pressure phase of sulfur (S-III). We find that the molecular O8 phase remains extremely stable in a large pressure range of 0.008 - 2 TPa, whose breakdown is driven by the pressure-induced instability of a transverse acoustic phonon mode at zone boundary, leading to the ultimate formation of \theta-O4. Remarkably, stabilization of \theta-O4 turns oxygen from a superconductor into an insulator with a wide band gap (approximately 5.9 eV) originating from the sp3-like hybridized orbitals of oxygen and the localization of valence electrons. (This is a pre-print version of the following article: Li Zhu et al, Spiral chain O4 form of dense oxygen, Proc. Natl. Acad. Sci. U.S.A. (2011), doi: 10.1073/pnas.1119375109, which has been published online at http://www.pnas.org/content/early/2011/12/27/1119375109 .)Comment: 13 apages, 3 figure