This dissertation is concerned with the relationship between accounting earnings and stock prices. It consists of three empirical papers, all using a sample of firms listed on the Stockholm Stock Exchange (1990-2008). The first paper documents the existence of a drift in stock prices subsequent to quarterly earnings announcements. Two interesting empirical observations are that the drift is only significant for longer holding periods and that the drift on the short position, i.e. after bad earnings news, is negligible. The lack of downward drift on the short position is interpreted as an indication of the post-earnings announcement drift, at least partly, being explained by investors demanding a compensation for a risk factor that is omitted in the test design. The second paper illustrates under what conditions information risk in the earnings signal might explain a low announcement reaction and a price drift in the post-announcement period. It is hypothesized that two earnings signals – based either on GAAP earnings or core earnings – have different levels of information uncertainty with respect to how they depict the value creation of the firm. In the empirical sections, it is concluded that the low immediate announcement reaction and high post-announcement drift for the GAAP earnings signal is due to this signal being perceived by investors as containing more uncertainty than the core earnings signal. It is argued that this uncertainty might be due to GAAP earnings encompassing items that prior research has shown more likely to be manipulated and/or to contain estimation error. The positive association between information risk and expected return is further investigated in the third paper, where information risk is measured by earnings quality metrics. Using a new approach to estimate the implied cost of capital, it is found that Swedish investors demand a higher expected return for firms with poor earnings quality, i.e. firms associated with higher information risk. / Diss. Stockholm : Handelshögskolan i Stockholm, 2011

Behaviour occurs in time, and precise timing in the range of seconds and fractions of seconds is for most living organisms necessary for successful interaction with the environment. Our ability to time discrete actions and to predict events on the basis of prior events indicates the existence of an internal timing mechanism. The nature of this mechanism provides essential constraints on models of the functional organisation of the brain. The present work indicates that there are discontinuities in the function of time close to 1 s and 1.4 s, both in the amount of drift in a series of produced intervals (Study I) and in the detectability of drift in a series of sounds (Study II). The similarities across different tasks further suggest that action and perceptual judgements are governed by the same (kind of) mechanism. Study III showed that series of produced intervals could be characterised by different amounts of positive fractal dependency related to the aforementioned discontinuities. In conjunction with other findings in the literature, these results suggest that timing of intervals up to a few seconds is strongly dependent on previous intervals and on the duration to be timed. This argues against a clock-counter mechanism, as proposed by scalar timing theory, according to which successive intervals are random and the size of the timing error conforms to Weber's law. A functional model is proposed, expressed in an autoregressive framework, which consists of a single-interval timer with error corrective feedback. The duration-specificity of the proposed model is derived from the order of error correction, as determined by a semi-flexible temporal integration span.

The concept of energy production through the fusion of two light nuclei has been studied since the 1950’s. One of the major problems that fusion scientists have encountered is the confinement of the hot ionised gas, i.e. the plasma, in which the fusion process takes place. The most common way to contain the plasma is by using at magnetic field configuration, in which the plasma takes a doughnut-like shape. Experimental devices of this kind are referred to as tokamaks. For the fusion process to proceed at an adequate rate, the temperature of the plasma must exceed 100,000,000C. Such a high temperature forces the plasma out of thermodynamical equilibrium which plasma tries to regain by exciting a number of turbulent processes. After successfully quenching the lager scale magnetohydrodynamic turbulence that may instantly disrupt the plasma, a smaller scale turbulence revealed itself. As this smaller scale turbulence behaved contrary to the common theory at the time, it was referred to as anomalous. This kind of turbulence does not directly threaten existents of the plasma, but it allows for a leakage of heat and particles which inhibits the fusion reactions. It is thus essential to understand the origin of anomalous turbulence, the transport it generates and most importantly, how to reduce it. Today it is believed that anomalous transport is due to drift-type waves driven by temperature and density inhomogeneities and the theoretical treatment of these waves is the topic of this thesis. The first part of the thesis contains a rigorous analytical two-fluid treatment of drift waves driven solely by density inhomogeneities. Effects of the toroidal magnetic field configuration, the Landau resonance, a peaked diamagnetic frequency and a sheared rotation of the plasma have been taken into account. These effects either stabilise or destabilise the drift waves and to determine the net result on the drift waves requires careful analysis. To this end, dispersion relations have been obtained in various limits to determine when to expect the different effects to be dominant. The main result of this part is that with a large enough rotational shear, the drift waves will be quenched. In the second part we focus on temperature effects and thus treat reactive drift waves, specifically ion temperature gradient and trapped electron modes. In fusion plasmas the α-particles, created as a by-product of the fusion process, transfer the better part of their energy to the electrons and hence the electron temperature is expected to exceed the ion temperature. In most experiments until today, the ion temperature is greater than the electron temperature and this have been proven to improve the plasma confinement. To predict the performance of future fusion plasmas, where the fusion process is ongoing, a comprehensive study of hot-electron plasmas and external heating effects have been carried out. Especially the stiffness (heat flux vs. inverse temperature length scale) of the plasma has been examined. This work was performed by simulations done with the JETTO code utilising the Weiland model. The outcome of these simulations shows that the plasma response to strong heating is very stiff and that the plasma energy confinement time seems to vary little in the hot-electron mode.

Diamond is a semiconductor with many superior material properties such as high breakdown field, high saturation velocity, high carrier mobilities and the highest thermal conductivity of all materials. These extreme properties, as compared to other (wide bandgap) semiconductors, make it desirable to develop single-crystalline epitaxial diamond films for electronic device and detector applications. Future diamond devices, such as power diodes, photoconductive switches and high-frequency field effect transistors, could in principle deliver outstanding performance due to diamond's excellent intrinsic properties. However, such electronic applications put severe demands on the crystalline quality of the material. Many fundamental electronic properties of diamond are still poorly understood, which severely holds back diamond-based electronic device and detector development. This problem is largely due to incomplete knowledge of the defects in the material and due to a lack of understanding of how these defects influence transport properties. Since diamond lacks a shallow dopant that is fully thermally activated at room temperature, the conventional silicon semiconductor technology cannot be transferred to diamond devices; instead, new concepts have to be developed. Some of the more promising device concepts contain thin delta-doped layers with a very high dopant concentration, which are fully activated in conjunction with undoped (intrinsic) layers where charges are transported. Thus, it is crucial to better understand transport in high-quality undoped layers with high carrier mobilities. The focus of this doctoral thesis is therefore the study of charge transport and related electronic properties of single-crystalline plasma-deposited (SC-CVD) diamond samples, in order to improve knowledge on charge creation and transport mechanisms. Fundamental characteristics such as drift mobilities, compensation ratios and average pair-creation energy were measured. Comparing them with theoretical predictions from simulations allows for verification of these models and improvement of the diamond deposition process.

Slutet av 1990-talet var början till slutet för många IT-företag när den så kallade IT-bubblan började spricka. Gemensam nämnare för de företag som överlevde var att de hade en genomtänkt strategi med en stabil ägarstruktur, god ledning, trogna kunder och stabil omsättning. Sedan december 2007 har tendenser visats att Sverige är på väg in i en lågkonjunktur som kommer att hålla i sig under 2008 och 2009. Med lågkonjunkturen följer även en minskad vilja att konsumera vilket leder till svårare tider för företag. Mot denna bakgrund, samt ett befintligt intresse för strategiarbete i små företag, inleddes studien med följande problemformulering: Hur bör små företag i en tillväxt arbeta för att förebygga strategisk drift? Syftet för studien var att förstå hur små företag i tillväxt arbetar med kontinuerliga strategifrågor samt att presentera rekommendationer för att motverka strategisk drift till de undersökta företagen. Studien är huvudsakligen genomförd med en retroduktiv ansats där det empiriska materialet sammanställdes, analyserades samt utformades till rekommendationer vilka presenterades för respondenterna. Urvalet av respondenter utgörs av tre små företag med god tillväxt. Det material som erhölls ur den empiriska undersökningen tolkades utifrån förförståelsen och den teoretiska referensramen varvid en delvis hermeneutisk och delvis realistisk kunskapssyn användes. Studien är av kvalitativ karaktär och datainsamlingen genomfördes med hjälp av intervjuer. Genom en sammanställning av vedertagna teoretiska resonemang skapades en referensram på vilken en matris baserades. Avsikten med matrisen var att skapa ett verktyg vilket innefattar de interna och externa aspekter som påverkar den strategiska positionen för företag. Matrisen kan även tydliggöra för hur olika strategiska beslut påverkar företaget i relation till de långsiktiga strategiska målen. Med stöd av den empiriska undersökningen positionerades företagen i matrisen utifrån deras nuvarande arbetssätt. Positionen motiverades för respondenterna som också presenterades ett möjligt framtida scenario rörande hur framtiden skulle kunna se ut om med den utveckling företaget hade för närvarande. Därefter presenterades ett alternativt scenario vilket, utifrån undersökningen och analysen, representerade en önskvärd utveckling för företagen. Rekommendationerna mottogs positivt av respondenterna vilket tolkades som att matrisen fyllt sitt syfte och befäste tanken att använda matrisen för scenarioskapande.

This study contributes to theory and public policy in Canada and globally. It uses mixed methodology and triangulation of evidence through policy documents(Bovey,Rae,Drummond),empirical studies and surveys(ranking,NSSE data,regression), CAUT/AUCC and Statistics Canada sources and qualitative sources - writings of university presidents (Bok,Kerr,Fallis),researchers (Rajagopal, Clark et al.)as well,talks with sessionals,teaching assistants and administrators. The framework consists of Altbach's four factors - democratization, the knowledge economy, globalisation and competition and three ideal types for university development - entrepreneurial, liberal education and deliberative. The thesis contrasts classical college with the modern university system. The results show strong evidence for research domination, mission drift and shift towards the entrepreneurial model. Quality is compromised by lowering requirements, compressed courses, less study time, large classes taught by sessionals and TAs, grade inflation and consumerist behaviour, while critical thinking and moral development are neglected.

The rapid depletion of hydrocarbon fields around the world has led the industry to search for these resources in ever increasing water depths. In this context, the large diameter (D > 100mm) vertical riser has become a subject of great interest. In this research work, a major investigation was undertaken to determine the two phase flow hydrodynamics in a 254mm vertical riser. Two types of experiments were performed for range of air-water superficial velocities. The first experimental campaign addresses the issue of the two gas injector’s performances (conventional vs. novel design gas injector) in the large diameter vertical riser. The experimental results show that the novel design gas injector should be the preferential choice. The second set of the experimental work investigates the two phase flow hydrodynamics in the vertical riser in detail. The two phase flow patterns and their transitions were identified by combination of visual observations and statistical features. Based on the results, the experimental flow regime map was developed and compared with the existing vertical upflow regime maps/models. None of the flow regime transition models adequately predicted the flow regimes transitions in large diameter vertical risers as a whole. In this regard, the Taitel et al. (1980) bubble to slug flow transition model has been modified for large diameter vertical upflow conditions, based on the physical mechanism observed. The general trends of modified criteria agreed well with the current and other large diameter experimental results. The effect of upstream conditions on the vertical riser flow behaviour was also investigated in detail by two different inlet configurations (i) near riser base injection and (ii) upstream flowline injection. It was found that no significant differences exist in flow behaviour at low air-water superficial velocities for both the inlet configuration, at high air-water superficial velocities, the intermittent flow behavior in flowline influences the riser flow pattern characteristics and thereby controls the riser dynamics. It is found that liquid slugs from the flowline naturally dissipate to some extent in the riser as a consequence of compression of succeeding bubble that rapidly expands and break through the liquid slug preceding it when it enters the riser. The experimental work corroborates the general consensus that slug flow does not exist in large diameter vertical upflow condition. Experimental data has been further compared to increase the confidence on the existing two phase flow knowledge on large diameter vertical riser: (a) by comparing with other experimental studies on large diameter vertical upflow in which generally, a good agreement was found, (b) by assessing the predictive capability of void fraction correlations/pressure gradient methods. The important implication of this assessment is that the mechanistic approach based on specific flow regime in determining the void fraction and pressure gradient is more successful than conventional empirical based approaches. The assessment also proposes a proposed set a of flow regime specific correlations that recommends void fraction correlations based on their performances in the individual flow regimes. Finally, a numerical model to study the hydrodynamic behaviour in the large diameter horizontal flowline-vertical riser system is developed using multiphase flow simulator OLGA. The simulated results show satisfactory agreement for the stable flows while discrepancies were noted for highly intermittent flows. The real time boundary application was partially successful in qualitatively reproducing the trends. The discrepancies between the predicted results and experimental data are likely to be related to the incorrect closure relations used based on incorrect flow regimes predictions. The existence of the multiple roots in the OLGA code is also reported for the first time.

This study contributes to theory and public policy in Canada and globally. It uses mixed methodology and triangulation of evidence through policy documents(Bovey,Rae,Drummond),empirical studies and surveys(ranking,NSSE data,regression), CAUT/AUCC and Statistics Canada sources and qualitative sources - writings of university presidents (Bok,Kerr,Fallis),researchers (Rajagopal, Clark et al.)as well,talks with sessionals,teaching assistants and administrators. The framework consists of Altbach's four factors - democratization, the knowledge economy, globalisation and competition and three ideal types for university development - entrepreneurial, liberal education and deliberative. The thesis contrasts classical college with the modern university system. The results show strong evidence for research domination, mission drift and shift towards the entrepreneurial model. Quality is compromised by lowering requirements, compressed courses, less study time, large classes taught by sessionals and TAs, grade inflation and consumerist behaviour, while critical thinking and moral development are neglected.

資料串流探勘是一個重要的研究領域，因為在現實中有許多重要的資料以串流的形式產生或被收集，金融市場的資料常常是一種資料串流，而通常這類型資料的本質是變動性大的。在這篇論文中我們運應了資料串流探勘的技術去預測台灣加權指數期貨的漲跌。對機器而言，預測期貨這種資料串流並不容易，而困難度跟概念飄移的種類與程度或頻率有關。概念飄移表示資料的潛在分布改變，這造成預測的準確率會急遽下降，因此我們專注在如何處理概念飄移。首先我們根據實驗的結果推測台灣加權指數期貨可能存在高頻率的概念飄移。另外實驗結果指出，使用偵測概念飄移的演算法可以大幅改善預測的準確率，甚至對於原本表現不好的演算法都能有顯著的改善。在這篇論文中我們亦整理出專門處理各類概念飄移的演算法。此外，我們提出了一個多分類器演算法，有助於偵測「重複發生」類別的概念飄移。該演算法相比改進之前，其最大的特色在於不需要使用者設定每個子分類器的樣本數，而該樣本數是影響演算法的關鍵之一。 / Data stream mining is an important research field, because data is usually generated and collected in a form of a stream in many cases in the real world. Financial market data is such an example. It is intrinsically dynamic and usually generated in a sequential manner. In this thesis, we apply data stream mining techniques to the prediction of Taiwan Stock Exchange Capitalization Weighted Stock Index Futures or TAIEX Futures. Our goal is to predict the rising or falling of the futures. The prediction is difficult and the difficulty is associated with concept drift, which indicates changes in the underlying data distribution. Therefore, we focus on concept drift handling. We first show that concept drift occurs frequently in the TAIEX Futures data by referring to the results from an empirical study. In addition, the results indicate that a concept drift detection method can improve the accuracy of the prediction even when it is used with a data stream mining algorithm that does not perform well. Next, we explore methods that can help us identify the types of concept drift. The experimental results indicate that sudden and reoccurring concept drift exist in the TAIEX Futures data. Moreover, we propose an ensemble based algorithm for reoccurring concept drift. The most characteristic feature of the proposed algorithm is that it can adaptively determine the chunk size, which is an important parameter for other concept drift handling algorithms.

I denna rapport har det utförts två fallstudier från två olika vindkraftsanläggningar och med hjälp av en utarbetad modell har livscykelkostnaderna jämförts för de två fallstudierna.Resultatet visade att livscykelkostnaden per producerad kWh sjunker allteftersom den installerade effekten blir högre.Kostnadsmodellen som utarbetats och tillämpats för resultaten har visat sig ha hög verifierbarhet då resultaten har varit jämförbara med litterära studier. / In this report, conducted two case studies from two wind farms and using an elaborate model, life cycle costs compared to the two case studies.The results showed that the lifecycle cost per kWh decreases as the installed power increases.Cost model as developed and applied to generate the reported results have been generated in the results that are comparable to literary studies.