Forskningen kring effektiva marknader är uppdelad; ena sidan påstår att marknaden är fullständigt effektiv och det inte går att skapa någon form av överavkastning. Andra sidan hävdar tvärtemot att endast historisk information reflekteras i dagens priser. På kort sikt kan det finns en viss ineffektivitet och de flesta erkänner att marknaden innehåller anomalier Syftet med denna studie är att undersöka om det existerar systematiska fel beträffande informationsflöden som pekar mot att den svenska aktiemarknaden inte är av semi-stark form eller stark form av effektivitet Vi utgår från tre metodologiska ställningstaganden; utgångspunkt, forskningsansats samt kunskapssyn. En deduktivt kvantitativ metod tillämpas och vi applicerar metoden för event study. Vi finner stöd för att det finns systematiska fel i marknaden beträffande informationsflöden i form av aktierekommendationer. Resultaten antyder att den svenska aktiemarknaden inte är av starkt effektiv form och i ett fall av fyra finner vi att den inte heller besitter semi-stark form. / Research concerning efficient markets are divided into two camps; the one hand, claims that the market is fully efficient and it is not possible to create any kind of excess returns. The other side argues the contrary that only historical information are reflected in today’s prices. Short term, there is some inefficiency and most recognize that the market contain anomalies The purpose is to investigate whether there exist indications regarding flows of information to the Swedish stock market suggesting a semi-strong form or strong form of efficiency. We start from three methodological statements; starting point, the research approach and epistemological beliefs. A deductive quantitative methodology is used, and we apply the method of event study. We find evidence for the existence of systematic errors in the market in terms of flows of information in the form of stock recommendations. The results suggest that the Swedish stock market is not of the strong efficient form and in one case out of four, we find that it does not possess the semi-strong form.

Hållbarhet är ett begrepp som har skiftande innebörd, både inom vetenskap och populärvetenskap. Forskning kring hållbarhet har ett särskilt fokus på kartläggning av orsakssamband och enbart ett fåtal studier fokuserar på att kartlägga och utforska hur begreppet hållbarhet konstrueras genom företags kommunikation. Inom redovisning efterfrågas ofta ett mer principbaserat och konceptuellt angreppssätt, och då detta enligt vår litteraturöversikt ges begränsat utrymme inom forskning kring hållbarhet, finns det möjligheter till att bidra med förståelse på området. Syftet med denna studie är att utforska hur begreppet hållbarhet kommuniceras och därmed konstrueras av företag med affärskonceptet fast fashion. Det finns en distinktion mellan handling och kommunikation och den här studien behandlar enbart kommunikationsaspekten. Vi har genomfört en kvalitativ innehållsanalys av hållbarhetsredovisningar för företag med affärskonceptet fast fashion. Studien har en tvärsnittsdesign med ett teoretiskt urval och top of mind-associationer. Totalt inkluderades tre företag i studien och deras respektive hållbarhetsredovisningar för rapporteringsåret 2013. I analysen har vi arbetat utifrån en abduktiv ansats inspirerat av ett foucauldianskt perspektiv. Den teoretiska modellen utvecklades med hjälp av tidigare litteratur om hållbarhetsdefinitioner och användes som en utgångspunkt för att kategorisera de textavsnitt som identifierades i respektive analys. Vår utforskning av företagens kommunikation av hållbarhet leder till slutsatsen att begreppet snarare konstrueras som produktiv aktivitet än handlingsklokhet i och med företagens tydliga fokus på stegvis anpassning och efterlevnad av såväl koder som specifika regler. Weak sustainability är mer framträdande än strong sustainability i företagens hållbarhetsrapportering, men det finns även en glidande skala mellan dessa. Till skillnad från övriga studier kring konstruktion av hållbarhetsbegreppet riktar denna studie in sig på företag med ett visst koncept (i.e. fast fashion) i utforskningen av hur hållbarhetsbegreppet kommuniceras och konstrueras. Studiens bidrag är utvecklandet av den teoretiska modellen i form av en glidande skala samt ökad konceptuell förståelse för konstruktion av hållbarhet. Vi argumenterar således för en glidande skala mellan de teoretiskt definierade hållbarhetskategorierna, medan andra studier enbart presenterar sina resultat enligt dikotomier. / Considering both science and popular science, sustainability is a concept of diverse meanings. Scientific research concerning sustainability has a particular focus on plotting causal links. Only a few studies focus on plotting and exploring the concept of sustainability as it is being conveyed by businesses via communication in corporate sustainability reports. Within the accounting field, there is a common demand for a principles-based and conceptual approach. Thus, while our literature review shows scientific research on sustainability has given limited attention to this approach, there are vast opportunities to contribute to this field by enhancing the comprehension of this issue. Consequently, the aim of this study is to explore the way in which the concept of sustainability is communicated and hence constructed by fast fashion businesses. As there is a distinction between practice and communication, this study merely focuses on the communication aspect.We have conducted a qualitative content analysis based on corporate sustainability reports issued by fast fashion corporations. The study applies a cross-sectional design and a theoretical sampling technique coupled with top-of-mind associations. In total, three corporations were included in this study, resulting in a sample of three corporate sustainability reports from the reporting year of 2013. During the analysis, an abductive approach inspired by a foucauldian perspective was applied. The theoretical model was elaborated on the basis of previous research and academic literature on the definition of sustainability and it served as an initial structure for categorization of the empirical observations.Our findings indicate that companies portray a clear focus on gradual adjustment and conformity to various codes as well as regulations, which leads to the conclusion that companies included in this study construct sustainability in terms of skills rather than wisdom. Furthermore, our findings point to the conclusion that elements of weak sustainability are more prominent than elements of strong sustainability in corporate sustainability reports. However, a notable finding is the existence of a sliding scale between these paradigms. As opposed to other studies regarding the construction of sustainability, this study focuses on a certain business concept (i.e. fast fashion) exploring the communication and construction of the concept sustainability. The contribution of our study is an evolution of the model in terms of a sliding scale and increased conceptual understanding of the term sustainability. We argue a sliding scale between weak and strong sustainability should be taken into account, while previous studies have presented their findings solely as dichotomies.This paper is written in Swedish.

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La collaboration en temps réel est un cas spécial de collaboration où les utilisateurs travaillent sur le même élément simultanément et sont au courant des modifications des autres utilisateurs en temps réel. Les données distribuées doivent rester disponibles et consistant tout en étant répartis sur plusieurs systèmes physiques. "Strong Consistency" est une approche qui crée un ordre total des opérations en utilisant des mécanismes tel que le "locking". Cependant, cela introduit un "bottleneck". Ces dix dernières années, les algorithmes de concurrence ont été étudiés dans le but de garder la convergence de tous les replicas sans utiliser de "locking" ni de synchronisation. "Operational Trans- formation" et "Conflict-free Replicated Data Types (CRDT)" sont utilisés dans ce but. Cependant, la complexité de ces stratégies les rend compliquées à intégrer dans des logicielles conséquents, comme les éditeurs de modèles, spécialement pour des data structures complexes comme les graphes. Les implémentations actuelles intègrent seulement des data linéaires tel que le texte. Dans ce mémoire, nous présentons CollabServer, un framework pour construire des environnements de collaboration. Il a une implémentation de CRDTs pour des data structures complexes tel que les graphes et donne la possibilité de construire ses propres data structures. / Real-time collaboration is a special case of collaboration where users work on the same artefact simultaneously and are aware of each other’s changes in real-time. Shared data should remain available and consistent while dealing with its physically distributed aspect. Strong Consistency is one approach that enforces a total order of operations using mechanisms, such as locking. This however introduces a bottleneck. In the last decade, algorithms for concurrency control have been studied to keep convergence of all replicas without locking or synchronization. Operational Transformation and Conflict free Replicated Data Types (CRDT) are widely used to achieve this purpose. However, the complexity of these strategies makes it hard to integrate in large software, such as modeling editors, especially for complex data types like graphs. Current implementations only integrate linear data, such as text. In this thesis, we present CollabServer, a framework to build collaborative environments. It features a CRDTs implementation for complex data types such as graphs and gives possibility to build other data structures.

<p>This doctoral thesis is comprised of four papers that all relate to the subject of Time Series Analysis.</p><p>The first paper of the thesis considers point estimation in a nonnegative, hence non-Gaussian, AR(1) model. The parameter estimation is carried out using a type of extreme value estimators (EVEs). A novel estimation method based on the EVEs is presented. The theoretical analysis is complemented with Monte Carlo simulation results and the paper is concluded by an empirical example.</p><p>The second paper extends the model of the first paper of the thesis and considers semiparametric, robust point estimation in a nonlinear nonnegative autoregression. The nonnegative AR(1) model of the first paper is extended in three important ways: First, we allow the errors to be serially correlated. Second, we allow for heteroskedasticity of unknown form. Third, we allow for a multi-variable mapping of previous observations. Once more, the EVEs used for parameter estimation are shown to be strongly consistent under very general conditions. The theoretical analysis is complemented with extensive Monte Carlo simulation studies that illustrate the asymptotic theory and indicate reasonable small sample properties of the proposed estimators.</p><p>In the third paper we construct a simple nonnegative time series model for realized volatility, use the results of the second paper to estimate the proposed model on S&P 500 monthly realized volatilities, and then use the estimated model to make one-month-ahead forecasts. The out-of-sample performance of the proposed model is evaluated against a number of standard models. Various tests and accuracy measures are utilized to evaluate the forecast performances. It is found that forecasts from the nonnegative model perform exceptionally well under the mean absolute error and the mean absolute percentage error forecast accuracy measures.</p><p>In the fourth and last paper of the thesis we construct a multivariate extension of the popular Diebold-Mariano test. Under the null hypothesis of equal predictive accuracy of three or more forecasting models, the proposed test statistic has an asymptotic Chi-squared distribution. To explore whether the behavior of the test in moderate-sized samples can be improved, we also provide a finite-sample correction. A small-scale Monte Carlo study indicates that the proposed test has reasonable size properties in large samples and that it benefits noticeably from the finite-sample correction, even in quite large samples. The paper is concluded by an empirical example that illustrates the practical use of the two tests.</p>

冷戰結束後，由於蘇聯的崩解，致使中亞地區權力出現真空狀態。中亞新興獨立的五個國家援引俄羅斯、美國、中國等外力，來協助國家的進步。俄羅斯自詡為中亞的保護者，並且認為中亞為其勢力範圍。美國為霸權擴張、西方式民主鼓吹者，致力於反恐戰爭與中亞資源的開發。中國的崛起需要的是中亞區域的穩定以及中亞各國與中國的相互合作。本研究試圖透過中亞本身內部安全、資源、民族、文化等因素以及外部國際環境變化，來探討俄、美、中三國與中亞五國之間的關係發展與演變。 / After the cold war, the disintegration of the Soviet Union has caused a power vacuum situation in Central Asia. The five newly independent Central Asian states have cited external forces, including Russia, the United States and China, to assist their own countries’ progress. Russia treats itself as Central Asia’s protector, and considers Central Asia under its sphere of influence. As a hegemony expansionist and western-style democracy promoter, the US strives for anti-terrorism and the extraction of natural resources in Central Asia. For China’s rise, China needs regional stability and maintains mutual cooperation with Central Asian states. This study explores Central Asian states’ relationship with Russia, America and China through domestic security, natural resources, nationalities, cultures, and international situation.

In this thesis, research on a-Si:H Schottky diodes and a-Si:H/c-Si heterojunctions is presented with the focus on the capacitance spectroscopy and information on electronic properties that can be derived from this technique. Last years a-Si:H/c-Si heterojunctions (HJ) have received growing attention as an approach which combines wafer and thin film technologies due to their low material consumption and low temperature processing. HJ solar cells benefit from lower fabrication temperatures thus reduced costs, possibilities of large-scale deposition, better temperature coefficient and lower silicon consumption. The most recent record efficiency belongs to Panasonic with 24.7% for a cell of 100 cm² was obtained. The aim of this thesis is to provide a critical study of the capacitance spectroscopy as a technique that can provide information on both subjects: DOS in a-Si:H and band offset values in a-Si:H/c-Si heterojunctions.The first part of the manuscript is devoted to capacitance spectroscopy in a-Si:H Schottky diodes. The interest is concentrated on the simplified treatment of the temperature and frequency dependence of the capacitance that allows one to extract the density of states at the Fermi level in a-Si:H. We focus on the study of the reliability and validity of this approach applied to a-Si:H Schottky barriers with various magnitudes and shapes of the DOS. Several structures representing n-type and undoped hydrogenated amorphous silicon Schottky diodes are modeled with the help of numerical simulation softwares. We show that the reliability of the studied treatment drastically depends on the approximations used to obtain the explicit analytical expression of the capacitance in such an amorphous semiconductor.In the second part of the chapter, we study the possibility of fitting experimental capacitance data by numerical calculations with the input a-Si:H parameters obtained from other experimental techniques. We conclude that the simplified treatment of the experimentally obtained capacitance data together with numerical modeling can be a valuable tool to assess some important parameters of the material if one considers the results of numerical modeling and performs some adjustments. The second part is dedicated to capacitance spectroscopy of a-Si:H/c-Si heterojunctions with special emphasis on the influence of a strong inversion layer in c-Si at the interface. Firstly, we focus on the study of the frequency dependent low temperature range of capacitance-temperature dependencies of a-Si:H/c-Si heterojunctions. The theoretical analysis of the capacitance steps in calculated capacitance-temperature dependencies is presented by means of numerical modeling. It is shown that two steps can occur in the low temperature range, one being attributed to the activation of the response of the gap states in a-Si:H to the small signal modulation, the other one being related to the response of holes in the strong inversion layer in c-Si at the interface. The experimental behavior of C-T curves is discussed. The quasi-static regime of the capacitance is studied as well. We show that the depletion approximation fails to reproduce the experimental data obtained for (p) a-Si:H/(n) c-Si heterojunctions. Due to the existence of the strong inversion layer, the depletion approximation overestimates the potential drop in the depleted region in crystalline silicon and thus underestimates the capacitance and its increase with temperature. A complete analytical calculation of the heterojunction capacitance taking into account the hole inversion layer is developed. It is shown that within the complete analytical approach the inversion layer brings significant changes to the capacitance for large values of the valence band offset. The experimentally obtained C-T curves show a good agreement with the complete analytical calculation and the presence of the inversion layer in the studied samples is thus confirmed.

We have acquired Hubble Space Telescope (HST) and Very Large Telescope near-infrared spectra and images of supernova (SN) Refsdal after its discovery as an Einstein cross in fall 2014. The HST light curve of SN Refsdal has a shape consistent with the distinctive, slowly rising light curves of SN. 1987A-like SNe, and we find strong evidence for a broad H alpha P-Cygni profile and Na I D absorption in the HST grism spectrum at the redshift (z = 1.49) of the spiral host galaxy. SNe. IIn, largely powered by circumstellar interaction, could provide a good match to the light curve of SN Refsdal, but the spectrum of a SN IIn would not show broad and strong H alpha and Na I D absorption. From the grism spectrum, we measure an H alpha expansion velocity consistent with those of SN. 1987A-like SNe at a similar phase. The luminosity, evolution, and Gaussian profile of the H alpha emission of the WFC3 and X-shooter spectra, separated by similar to 2.5 months in the rest frame, provide additional evidence that supports the SN. 1987A-like classification. In comparison with other examples of SN. 1987A-like SNe, photometry of SN Refsdal favors bluer B - V and V - R colors and one of the largest luminosities for the assumed range of potential magnifications. The evolution of the light curve at late times will provide additional evidence about the potential existence of any substantial circumstellar material. Using MOSFIRE and X-shooter spectra, we estimate a subsolar host-galaxy metallicity (8.3 +/- 0.1 dex and <8.4 dex, respectively) near the explosion site.

Cooperation in joint enterprises poses a social dilemma. How can altruistic behavior be sustained if selfish alternatives provide a higher payoff? This social dilemma can be overcome by the threat of sanctions. But a sanctioning system is itself a public good and poses a second-order social dilemma. In this paper, we show by means of deterministic and stochastic evolutionary game theory that imitation-driven evolution can lead to the emergence of cooperation based on punishment, provided the participation in the joint enterprise is not compulsory. This surprising result - cooperation can be enforced if participation is voluntary - holds even in the case of 'strong altruism', when the benefits of a player's contribution are reaped by the other participants only. (authors' abstract)

An odd open dominating set of a graph is a subset of the graph’s vertices with the property that the open neighborhood of each vertex in the graph contains an odd number of vertices in the subset. An odd closed r-dominating set is a subset of the graph’s vertices with the property that the closed r-ball centered at each vertex in the graph contains an odd number of vertices in the subset. We first prove that the n-fold direct product of simple graphs has an odd open dominating set if and only if each factor has an odd open dominating set. Secondly, we prove that the n-fold strong product of simple graphs has an odd closed r-dominating set if and only if each factor has an odd closed r-dominating set.