In this thesis we take the Bayesian persuasion model, impose a limitation on the signal space and subsequently derive the first order conditions for the equilibrium. Then we enhance the model for several different constraints. We find that the analysis is greatly facilitated if such constraints do not relax when more signals are added to the model. The first type of constraint is imposed to eliminate the perfectly informative persuasion mechanisms. The second type of constraint limits the total uncertainty reduction caused by the persuasion. Finally the third type of constraint is a participation constraint. It ensures a certain level of reservation utility for the persuaded party. Powered by TCPDF (www.tcpdf.org)

Imperfect Personality in Commercial Law Robert Pelikán Abstract In the theory of law, legal personality (the terms "legal person" and "legal personality" are used in this text in their continental sense, i.e. describing both non-human and human entities and their legal capacity) is usually seen as a simple quality having only values, true or false. The existing theories of legal personality were, therefore, trying to find such characteristics of legal personality, which will fully describe all legal persons existing in practice. Such an effort had to fail or, more precisely, the process of search for such a common denominator had to result in the disappearance of all the key characteristics necessary for understanding of the phenomenon of legal personality. The exploration of legal personality must hence begin with the finding that legal personality is not a quality having only values - true or false - but rather a full scale of values from nil to a (rarely seen) full legal personality, moreover appearing in many dimensions. In order to duly explain the phenomenon, the theory must not search for a common denominator of existing persons, but describe the concept of full legal personality and explain the consequences of imperfection of existing legal persons in any of such qualities. Those requirements cannot...

Essa dissertação foi desenvolvida com o objetivo de responder ao seguinte problema de pesquisa: há indícios de que notas explicativas das demonstrações financeiras que sejam menos compreensíveis, na visão de profissionais de investimento, conduzem a custos de transação maiores no estabelecimento de contratos? Por custos de transação, entendem-se aqueles referentes à coleta de informações, os custos de negociação e os de estabelecimento de contratos (COASE, 1991). Uma informação de difícil compreensibilidade, portanto, seria um catalisador de novos custos de transação, trazendo ineficiências no estabelecimento de contratos futuros. Para atingir os objetivos desejados, foram distribuídos questionários aos profissionais de investimento no 22º Congresso APIMEC que foi realizado nos dias 30 a 31 de agosto de 2012. Do total de participantes, 54 pessoas responderam o mesmo. De modo geral, verificou-se que sob a situação de tempo escasso e um grande custo de decodificação das notas explicativas, o que aumenta os custos de transação, pode-se conjecturar que algumas análises estejam sendo feitas de modo ineficiente, o que poderia conduzir a ineficiências no estabelecimento de contratos futuros. Verificou-se também que há indícios de que há excesso de informações e não falta das mesmas, o que conduziria a problemas de informação imperfeita e não de informação incompleta (LOPES, 2008). / This dissertation was developed in order to answer the following research problem: Is there evidence that the explanatory notes in the financial statements that are less understandable, by the investment professionals point of view, lead to higher transaction costs in establishing contracts? For transaction costs, we understood those that are related to information collection, the costs of negotiating and establishing contracts (COASE, 1991). A difficult understandability of information would therefore be a catalyst of new transaction costs, bringing inefficiencies in establishing future contracts. To achieve the desired goals, questionnaires were distributed to investment professionals in 22º Congresso Apimec that was held on 30 to 31 August 2012. Of all participants, 54 people responded it. In general, it was found that under the situation of limited time and a large cost to decode the notes, which increases transaction costs, it can be conjectured that some analyzes are being done inefficiently, which might lead inefficiencies in the establishment of futures contracts. It was also found that there is evidence that there is too much information and not lack of them, which would lead to problems of imperfect information and not incomplete information (LOPES, 2008).

CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / Esta dissertaÃÃo aborda o comportamento semÃntico-discursivo do Aspecto verbal nas formas simples dos tempos: PretÃrito Perfeito e PretÃrito Imperfeito do modo Indicativo, em um corpus de seis inquÃritos do Banco de Dados PORCUFORT - PortuguÃs Oral Culto de Fortaleza. A fundamentaÃÃo teÃrica deste trabalho retoma algumas das principais pesquisas feitas, anteriormente, a respeito do Aspecto verbal; um estudo que trata da maneira como esta categoria à vista dentro da SemÃntica e do Discurso; alÃm da questÃo da referÃncia desta categoria no discurso e dos elementos lingÃÃsticos que, geralmente, auxiliam na sua caracterizaÃÃo, como: os circunstanciadores temporais e os argumentos do verbo. Na metodologia, apresentamos os fatores de anÃlise, quais sejam: parÃmetros de transitividade, tipos de verbo, figura e fundo e tipos de interpretaÃÃo. Assim, conseguimos perceber que esta categoria verbal possui caracterÃsticas semÃntico-discursivas que sÃo condicionadas nÃo apenas pela forma lexical ou morfÃmica dos verbos, mas tambÃm pelos argumentos que os acompanham e pelo contexto discursivo no qual estÃo inseridos. / This paper approaches the semantic-discursive behavior of the verbal Aspect in the simple forms of the tenses: Perfect Past and Imperfect Past of the Indicative mode, in a corpus of six inquiries of the database PORCUFORT - PortuguÃs Oral Culto de Fortaleza. The theoretical chapters of this work retake some of the main researches made, previously, regarding the verbal Aspect; a study that adopts the way as this category is seen inside of the Semantics and of the Speech; in addition to the subject of the reference of this category in the speech and of the linguistic elements that, generally, that aid in its characterization, like the adverbs of time and the verbs argument. In the methodology, we show the analysis factors, they are: parameters of transitivity, verb types, foreground and background, and interpretation types. Thus, we have noticed that this verbal category possesses semantic-discursive characteristics that are not just conditioned by the morphological or lexical form of the verbs, but also by the arguments that accompany them, and by the discursive context in which they are inserted.

The starting point in industrial organization is the notion of perfect competition. In a market with perfect competition, everything is transparent. In particular, there is perfect information about price, product value and firms' actions. This dissertation deals with exceptions from the world of perfect competition. The first two essays deal with imperfect information about prices and firms' actions, whereas the third essay considers imperfect information about the value of the traded goods. The first essay "Transparency and Competition" asks the question If prices are more or less transparent, does that favour consumers or producers? Starting from a search model, where some consumers know prices and other have to search, it is shown that a greater price transparency, i.e. a lower search cost, reduces the price in a single play of the game. When the game is repeated, however, the lower is the search cost, the easier it is to sustain collusion. Thus, promoting greater price transparency reduces the price in the stage game at the risk of increased opportunity for collusion. The second essay "Does Advertising Prevent Collusion?" analyses the case when firms can transmit price information to consumers by advertising. In contrast to the first essay, improved price transparency through advertising always reduces the price. It is even shown that the mere possibility of advertising can reduce the price, when firms are colluding. Thus, it is important to distinguish between advertising by firms and price publication by a third party. The first fosters competition, whereas thesecond may be harmful. In the third essay "Underwriter Competition" it is not the price that is more or less transparent. Instead, we consider a situation where sellers cannot transfer knowledge about their product values to the buyers. In order to overcome this problem, sellers may hire a renowned third party, an underwriter, who can certify that the products are of a certain value. The question that is posed in this essay is What happens if sellers can chose between different underwriters? It is shown that the underwriter market is a natural monopoly, where the underwriter with the highest ability toassess the value of the products gets the whole market. / Diss. Stockholm : Handelshögskolan, 2001

Wireless communication links with multiple antennas at both the transmitter and the receiver sides, so-called multiple-input-multiple-output (MIMO)systems, are attracting much interest since they can significantly increase the capacity of band-limited wireless channels to meet the requirements of the future high data rate wireless communications. The treatment of channel state information (CSI) is critical in the design of MIMO systems. Accurate CSI at the transmitter is often not possible or may require high feedback rates, especially in multi-user scenarios. Herein, we consider the robust design of linear transceivers with imperfect CSI either at the transmitter or at both sides of the link. The framework considers the design problem where the imperfect CSI consists of a channel mean and an channel covariance matrix or, equivalently, a channel estimate and an estimation error covariance matrix. For single-user systems, the proposed robust transceiver designs are based on a general cost function of the average mean square errors. Under different CSI conditions, our robust designs exhibit a similar structure to the transceiver designs for perfect CSI, but with a different equivalent channel and/or noise covariance matrix. Utilizing majorization theory, the robust linear transceiver design can be readily solved by convex optimization approaches in practice. For multi-user systems, we consider both the communication link from the users to the access point (up-link) as well as the reverse link from the access point to the users (down-link). For the up-link channel, it is possible to optimally design robust linear transceivers minimizing the average sum mean square errors of all the data streams for the users. Our robust linear transceivers are designed either by reformulating the optimization problem as a semidefinite program or by extending the design of a single-user system in an iterative manner. Under certain channel conditions, we show that the up-link design problem can even be solved partly in a distributed fashion. For the down-link channel, a system with one receive antenna per user is considered. A robust system design is obtained by reducing the feedback load from all users to allow only a few selected users to feed back accurate CSI to the access point. We study the properties of four typical user selection algorithms in conjunction with beamforming that guarantee certain signal-to-interference-plus-noise ratio (SINR) requirements under transmit power minimization. Specifically, we show that norm-based user selection is asymptotically optimal in the number of transmitter antennas and close-to-optimal in the number of users. Rooted in the practical significance of this result, a simpler down-link system design with reduced feedback requirements is proposed. / QC 20100922

This study shows a way of using pictures as a support in the teaching of a certain phenomenonin Spanish grammar, namely the difference between the imperfect and the preterite. The aimof this essay is to show that using pictures can actually benefit the students in theirunderstanding of this grammatical feature.The study is carried out with 54 Swedish upper secondary students. The studyconsists of a test and a questionnaire that the students had to do (the test was done twice).Between the two tests we explained the difference between the imperfect and the preterite,using pictures supporting our explanations. The results of the two tests were then compared inorder to see if the teaching with pictures had helped the students in their understanding of thedifference between these two time aspects. The results show that there is a clear improvementin the students’ knowledge after having seen the pictures that explain this phenomenon.The answers of the questionnaire were used to find out whether there are outer andinner factors that also affect the results of the test. For example, students that prefer to readreached higher results than students that prefer to speak. Their previous grades in the coursesalso affect the results in the way that students with higher grades reached higher results, ingeneral, though there were a few exceptions where students with lower grades actuallysurpassed their peers with higher grades. The results also show that it is easier for the studentsto understand which tense to use if the verbs are part of a bigger context.

This dissertation consists of two essays examining formal and informal long term health insurance markets. The first essay analyzes heterogeneity of Long-Term Care Insurance policyholders in their lapse decision, and how their ex-ante and ex-post subjective beliefs about the probability of needing Long-Term Care affect their lapse decisions. In this essay, I develop a model of lapse decision in a two-period insurance framework with a Bayesian learning process and implement several empirical specifications of the model using longitudinal data from the Health and Retirement Study. The results show that policyholders' ex- ante point predictions of their probabilities and their uncertainties about them have a persistent but declining impact on lapse decisions. Those who believe that their risk is higher are indeed more likely to remain insured. However, as their uncertainties surrounding their ex-ante point predictions increase, their chances of lapsing increase regardless of their initial perception biases. These results are heterogeneous across cohorts and policyholders and, in particular, show that those in the older group near the average age of Nursing Home entry have a precise prediction of their risk levels compared to the younger cohort. Policy simulations show that a more informed initial purchase decision reduces the chance of lapsing down the road. The second essay examines the extent to which informal risk sharing arrangement provides insurance against health shocks. I develop a comprehensive model of informal risk sharing contract with two-sided limited commitment which extends the standard model to a regime with the following features. Information regarding the nature of realized health shocks is imperfect and individuals' health capital stock serves as a storage technology and is a factor of production. The theoretical results show that, in such a regime, Pareto optimal allocations are history dependent even if participation constraints do not bind. I perform numerical analysis to show that risk sharing against health shock is less likely to be sustainable among non-altruistic individuals with different levels of biological survival rates and health capital productivity. The results also show that optimal allocations vary depending on the set of information available to individuals. Using panel data of households from villages in rural Ethiopia, I test the main predictions of the theoretical model. While there is negative history dependence in transfers among non-altruistic partners, history dependence is positive when risk sharing is along bloodline and kinship. However, neither short-term nor long-term health shocks are insured through informal risk sharing arrangements among non-altruistic individuals.

The high deployment and maintenance costs of last mile wireline networks (i.e., DSL and cable networks) have urged service providers to search for new cost-effective solutions to provide broadband connectivity. Broadband wireless access (BWA) networks, which offer a wide coverage area and high transmission rates in addition to their fast and low-cost deployment, have emerged as an alternative to last mile wireline networks. Therefore, BWA networks are expected to be deployed in areas with different terrain profiles (e.g., urban, suburban, rural) where wireless communication faces different channel impairments. This fact necessitates the adoption of various transmission technologies that combat the channel impairments of each profile. Implementation scenarios of BWA networks considered in this thesis are multicarrier-based direct transmission and single carrier-based cooperative transmission scenarios. The performance of these transmission technologies highly depends on how resources are allocated. In this thesis, we focus on the development of practical resource allocation schemes for the mentioned BWA networks implementation scenarios. In order to develop practical schemes, the imperfection of channel state information (CSI) and computational power limitations are among considered practical implementation issues. The design of efficient resource allocation schemes at the MAC layer heavily relies on the CSI reported from the PHY layer as a measure of the wireless channel condition. The channel estimation error and feedback delay renders the reported CSI erroneous. The inaccuracy in CSI propagates to higher layers, resulting in performance degradation. Although this effect is intuitive, a quantitative measure of this degradation is necessary for the design of practical resource allocation schemes. An approach to the evaluation of the ergodic mutual information that reflects this degradation is developed for single carrier, multicarrier, direct, and cooperative scenarios with inaccurate CSI. Given the CSI estimates and estimation error statistics, the presented evaluation of ergodic mutual information can be used in resource allocation and in assessing the severity of estimation error on performance degradation. A point-to-multipoint (PMP) network that employs orthogonal frequency division multiple access (OFDMA) is considered as one of the most common implementation scenarios of BWA networks. Replacing wireline networks requires not only providing the last mile connectivity to subscribers but also supporting their diverse services with stringent quality of service (QoS) requirements. Therefore, the resource allocation problem (i.e., subcarriers, rate and power allocation) is modeled as a network utility maximization (NUM) one that captures the characteristics of this implementation scenario. A dual decomposition-based resource allocation scheme that takes into consideration the diversity of service requirements and inaccuracy of the CSI estimation is developed. Numerical evaluations and simulations are conducted to validate our theoretical claims that the scheme maximizes resource utilization, coordinates with the call admission controller to guarantee QoS, and accounts for CSI inaccuracy. Cooperation has recently received great attention from the research community and industry because of its low cost and fast deployment in addition to the performance improvement it brings to BWA networks. In cooperative scenarios, subscribers cooperate to relay each other's signals. For this implementation scenario of BWA networks, a robust and constrained Kalman filter-based power allocation scheme is proposed to minimize power consumption and guarantee bit error probability (BEP) requirements. The proposed scheme is robust to CSI inaccuracy, responsive to changes in BEP requirements, and optimal in allocating resources. In summary, research results presented in this thesis contribute to the development of practical resource allocation schemes for BWA networks.

Global illumination is an important factor when striving for photo realism in computergraphics. This thesis describes why this is the case, and why global illumination is considered acomplex problem to solve. The problem becomes even more demanding when considering realtime purposes. Resent research has proven it possible to produce global illumination in realtime. Therefore the subject of this thesis is to compare and evaluate a number of those methods. An implementation is presented based on the Imperfect shadow maps method, which per se isbased on instant radiosity and reflective shadow maps. The implementation is able to renderplausible global illumination effects in real time, for fully dynamic scenes. With conclusions that while it demonstrably is possible to provide believable global illum-ination in real time, it is not without shortcomings. In every case approximations or restrictionshas to be done to some extent, sometimes leading to wrong results. Though in most cases, notvisually unpleasing by a great deal. The final conclusion is that global illumination is possible on current hardware, with believablequality and good speed. Showing great potential for future implementations on next generationof hardware.