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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
51

Aplicações da expansão de Edgeworth à precificação de derivativos financeiros / Testing option pricing with the Edgeworth expansion

Balieiro Filho, Ruy Gabriel 19 February 2003 (has links)
O Objetivo deste trabalho é usar uma ferramenta matemática conhecida como expansão de Edgeworth em conjunto com a moderna teoria de análise de derivativos financeiros que utilizam o método de precificação neutra ao risco. Tal expansão permite obter uma função densidade de probabilidade com assimetria e curtose arbitrárias a partir de uma densidade normal. Desta forma, podemos usar esta nova distribuição como a state price density do ativo-objeto procurando corrigir o sorriso da volatilidade através da definição de funções de probabilidade com assimetrias positivas ou negativas e curtose maior de que três. Além disso esperamos também chegar a uma nova maneira de realizar o delta hedge de uma carteira de replicação de modo mais eficiente do que a de Black-Scholes. / There is a well-developed framework, the Black?Scholes theory, for the pricing of contracts based on the future prices of certain assets, called options. This theory assumes that the probability distribution of the returns of the underlying asset is a Gaussian distribution. However, it is observed in the market that this hypothesis is 2awed, leading to the introduction of a fudge factor, the so-called volatility smile. Therefore, it would be interesting to explore extensions of the Black?Scholes theory to non-Gaussian distributions. In this paper, we provide an explicit formula for the price of an option when the distributions of the returns of the underlying asset is parametrized by an Edgeworth expansion, which allows for the introduction of higher independent moments of the probability distribution, namely skewness and kurtosis. We test our formula with options in the Brazilian and American markets, showing that the volatility smile can be reduced. We also check whether our approach leads to more e6cient hedging strategies of these instruments.
52

Evaluation of a K-5 mathematics program which integrates children's literature: classroom environment and attitudes

Mink, Deborah V. January 2002 (has links)
This thesis describes a one-year study of 120 fifth grade students whose teachers participated in a program entitled Project SMILE (Science and Mathematics Integrated with Literary Experiences). The purpose of the study was to investigate the extent to which the classroom implementation of Project SMILE positively influenced the classroom environment and student attitudes toward reading, writing and mathematics. This was accomplished by, first, facilitating a series of five professional development workshops with the teachers and, subsequently, asking these teachers to use the strategies with their students. Because Project CRISS (CReating Independence through Student-owned Strategies), the foundation of SMILE, had already proven to be successful nationwide for secondary students, this study focused on elementary (K-5) school students and their teachers. My evaluation of this unique program, that integrates children's literature and mathematics, focused on student attitudes and the nature of the classroom learning environment. My research represents one of the relatively few studies that have employed learning environment dimensions with students in the elementary school mathematics classroom as criteria of effectiveness in the evaluation of educational innovations. The My Class Inventory (MCI) and an adaptation of the 1988 NAEP (National Assessment of Educational Progress) Attitude Survey were administered to a sample of 120 Grade 5 students as measures of students' perceptions of the classroom learning environment and their attitudes. Qualitative data were composed of student and teacher interviews, classroom observations and work samples. Methodologically, my study supports previous research that successfully combined qualitative and quantitative methods of data collection. / The learning environment and attitude scales exhibited satisfactory internal consistency reliability and discriminant validity; additionally, the actual form of most learning environment scales was capable of differentiating between the perceptions of students in different classrooms. The implementation of SMILE was found to have a positive impact on the students and classes of the teachers who participated in the inservice program. In particular, students' attitudes to mathematics and reading improved, and there was congruence between students' actual and preferred classroom environment on the scales of satisfaction and difficulty. Therefore, others can implement SMILE with confidence. As well, prior research was replicated in that students' satisfaction was greater in classrooms with a more positive learning environment, especially in terms of student cohesiveness.
53

Calculating sensitivities in the SABR/LIBOR market model for European swaptions / Beräkna känsligheter under SABR/LIBOR modellen för Europeiska swaptioner

Hållberg, Moa January 2012 (has links)
This article presents a new approach for calculating sensitivities of European swaptions. The sensitivities are found by applying an adjoint method to a stochastic volatility model, namely the SABR/LIBOR market model. This market model predicts the volatility smile and follows the market fluctuations more accurately than earlier used deterministic volatility market models for complex derivatives. The new adjoint method involves not only sensitivity calculations, it also presents a way of estimating the time discretization error using an a posteriori approach. The error calculation is described in this document but not investigated further. The first step in order to calculate the sensitivities is to calibrate the SABR/LIBOR market model to some market data. In our calculations we used data from June 15 2011 with 6 month intervals between the maturity times. When this calibration is complete all of the parameters in the SABR/LIBOR market model are specified and we can continue with the sensitivity calculations using the new adjoint method. The results from these calculations show that the method is a good choice for estimating sensitivities if we consider a complex financial derivative like the European swaption. The method is quite computational so we recommend that it is only used on a small number of securities with respect to a large number of parameters. The method provides more market-driven price and sensitivity estimations than earlier used methods and can benefit hedging of portfolios.
54

Edgeworth 級數在選擇權定價之應用及實證研究 / Option pricing using Edgeworth series with empirical study

黃國倫, Huang,kuo lun Unknown Date (has links)
被廣泛應用在選擇權定價的Black-Scholes 模型[3] 時常在深價內與深價外 的選擇權價格有錯價的現象,也就是理論價格估計實際市場價格的偏差。藉由 Black-Scholes 評價公式所反推出的隱含波動度往往不像我們所期待的在不同履約價格具有一致性,這種現象被稱為波動度的微笑曲線。在這份論文裡,我們參考Jarrow and Rudd [13] 提出的方法,將Edgeworth展開式套用在Black-Scholes模型作延伸應用,進而推導出偏態峰態修正後的的評價公式,再利用台指選擇權的市場資料作實證分析並與Filho and Rosenfeld [1] 的研究作比較。我們發現從台指選擇權的實證結果得到非常態分配的隱含偏態和隱含峰態。此外,理論價格的估計偏誤比例顯著的被新的模型改善且隱含波動度的微笑曲線也變的較為平坦,這個方法提供我們一個有效的方法,利用標的資產的偏態峰態得到該資產的近似分配。 / The Black-Scholes [3] option pricing model widely applied in option contracts frequently misprices deep-in-the-money and deep-out-of-the-money options. The implied volatilities computed by the Black-Scholes formula are not identical on each strike price as we expect. This phenomenon is called the volatility smile or skew. In this thesis, we derived a skewness- and kurtosis-adjusted option pricing model using an Edgeworth expansion constructed by Jarrow and Rudd [13] to an investigation of TAIEX option prices and compare the results with those in Filho and Rosenfeld [1]. We found that non-normal skewness and kurtosis are implied by TAIEX option returns. Moreover, the magnitude of price deviations were signicantly corrected and the volatility skew is attened. This approach provides an useful way to derive an approximate distribution of a underlying security with its skewness and kurtosis.
55

Ontogênse do sorriso no contexto da interação mãe-bebê / Smile's ontogeny in the mother-infant interaction context

Deise Maria Leal Fernandes Mendes 12 March 2008 (has links)
Fundação de Amparo à Pesquisa do Estado do Rio de Janeiro / Esta tese teve como objetivos: (I) propor uma articulação teórica para o estudo do sorriso contemplando a dimensão histórica, sociocultural e evolutiva da espécie humana e seu aparato biológico; (II) realizar dois estudos empíricos, um longitudinal, da terceira semana ao sexto mês de vida de dois bebês e outro transversal, com bebês de um, dois e cinco meses de nascidos, com o propósito de: (II.1) investigar se há algum padrão de sorrisos em termos de freqüência, duração e características morfológicas, e se ocorrem transformações nesse padrão nos seis primeiros meses de vida; (II.2) analisar padrões de sorriso apresentados na presença de comportamentos afetivos da mãe, nesse período; e (II.3) verificar se os bebês respondem de modo contingente, com sorrisos, aos comportamentos afetivos da mãe, e se há padrões diferenciados por tipo de sorriso. Participaram do estudo longitudinal duas díades mãe-bebê, filmadas em suas residências, semanalmente. Do estudo transversal, para cada grupo de diferentes idades, participaram vinte díades mãe-bebê, também filmadas em suas residências. As categorias de observação, comuns aos dois estudos, foram codificadas em duas partes, sendo a referente aos sorrisos do bebê com comportamentos mutuamente exclusivos e exaustivos. Os índices de Kappa de Cohen e de concordância indicaram boa fidedignidade entre os observadores. Entre outras evidências, verificou-se tendência de trajetória de curva ascendente para os sorrisos dos bebês no período estudado, F(1,22) = 6,77, p<0,05, para um dos bebês do estudo longitudinal, e, F(1,23) = 7,85, p<0,05, para o outro. Os dois bebês revelaram uma tendência particular a exibir com mais freqüência um ou dois tipos de sorrisos. Os sorrisos da mãe, como demais comportamentos afetivos, mostraram-se potenciais eliciadores de sorrisos de tipos variados nos bebês. Correlações significativas foram encontradas, na pesquisa longitudinal, entre os tipos mais freqüentes de sorrisos dos bebês e os sorrisos de suas mães (r=0,77, p<0,0017, para um dos bebês, e r=0,62, p<0,0017, para o outro). Também no estudo transversal foi verificada correlação entre o sorriso simples e o sorriso da mãe (r=0,70, p<0,0007). Sorrisos de diferentes tipos foram exibidos pelos bebês, tanto no estudo longitudinal, quanto no transversal, como respostas contingentes aos comportamentos maternos observados. Esses e outros resultados indicam uma associação significativa entre os sorrisos dos bebês e comportamentos afetivos das mães. A relevância da temática desse trabalho contrasta com a carência de estudos brasileiros sobre o tema. Entende-se que essa lacuna precisa ser superada, e esta tese representou um movimento nessa direção. / This doctoral dissertation had the following purposes: (I) to propose an approach to the study of smile that integrates a historical, socio-cultural and evolutionary, and biological dimmension; (II) to carry out two empirical studies, the first one longitudinal, reaching from the third week to the sixth lifes month of two babies, and the second one, a transversal studie, at the first, the second and the fifth months of life, with the proposition of: (II.1) to investigate any eventual standard of smile exibition in terms of frequency, duration and morfological characteristics, and any possible transformation in this standard during the first six months of life; (II.2) to analyze the smile standards observed in the presence of mothers affective behaviors during the first six months of life; and (II.3) to verify if the babies can answer contingently, with smiles, to the mothers affectives behaviors, and also if there are specific standards for each kind of smile. Two mothers and their babies participated in the longitudinal study and were videotaped at home. Twenty mothers and their babies participated, for each of the three groups of different ages in the transversal study, and were videotaped at home. The observation categories in these two studies are codified in two parts. The first part had mutually exclusive and exhaustive behaviors (babys smiles). The Cohens Kappa and the agreement indexes indicated good reliability inter observers. Among the evidences, it was verified a incrising curve trajetorial tendency for the babiess smiles in the period studied, F(1,22) = 6,77, p<0,05 for the first baby, and F(1,23) = 7,85, p<0,05 for the second one, both of them in the longitudinal study context. The two babies have revealed a particular tendency to frequentely display one or two kinds of smile. Babies also answered contingently with smiles to mothers affective behaviors in the two studies. In the longitudinal resourch, correlations between the more frequent kinds of the babies smiles and his mothers smiles were verified (r=0,77, p<0,0017 for one baby, and r=0,62, p<0,0017 for the other). In the transversal research, correlations between the simple smile and the mothers smile were verified (r=0,70, p<0,0007). Differents kinds of smiles have been exibited from the babies, in the both studies, longitudinal and transversal, as contigencial anwers to the mothers observed behaviors. This and others results sinalize to an association between the babies smile and his mothers affective behaviors. The relevance of investigating babiessmile contrats with the lack of Brazilian studies on this theme. This dissertation intended to contributeas an effort to supply this gap.
56

A influ?ncia do sorriso gengival no vedamentos labial

Santos, Giselle Gasparino dos 11 December 2006 (has links)
Made available in DSpace on 2014-12-17T14:13:58Z (GMT). No. of bitstreams: 1 GiselleGS.pdf: 211619 bytes, checksum: 6067524ca70f63167077629a96864d9a (MD5) Previous issue date: 2006-12-11 / Ideally the smile should expose minimal gingival, therefore patients with gummy smile and passive eruption altered or excessive marginal gingivae, usually excessive gingival display because incomplete anatomical crown exposure is present. If the maxillary incisor show at rest is optimal, active upper incisor intrusion should not be iniciated. To achieve a smile with minimal gingival exposure, the anatomic crown should be fully exposed by surgical crown lengthening. Precise determination of the location of cementoenamel junction prior to surgery, precise placement of incisions and correct establish of biological width are necessary in order to achive this goal. One protocol is decribed and clinical results from 15 brazilian subjects, after three years post surgery are showed / Este projeto consagrou o encontro de duas ?reas do conhecimento: Periodontia e Fonoaudiologia, sendo o mesmo orientado por uma cirurgi? dentista, doutora em Odontologia e realizado por uma fonoaudi?loga mestre em Dist?rbios da Comunica??o. Os experimentos foram realizados por uma equipe multidisciplinar, composta por fonoaudi?logo e cirurgi?es dentistas que buscaram a rela??o em indiv?duos portadores de sorriso gengival e as implica??es miofuncionais orais. Objetivo: A proposta deste estudo foi verificar a influ?ncia do sorriso gengival no vedamento labial. Metodos: 18 indiv?duos com sorriso gingival e dificuldade no vedamento labial foram submetidos a avali??o oromiofuncional e eletromiografia de superf?cie parea verificar o esfor?o do m?sculo mentual para a realiza??o do vedamento labial nas condi??es pr? e p?s cir?rgica. Foi realizada cirurgia periodontal para remover o excesso de tecido gengival e/ou volume ?sseo da pr?-maxila e, ap?s 6 meses os pacientes foram reavaliados. Resultados: Diminui??o da contra??o e tens?o do musculo mentual foi clinicamente observado durante o vedamento labial e a an?lise eletromiogr?fica revelou uma diferen?a estatisticamente significante (27.67 ?RMS - 6.46 ?RMS, p=0.004) no esfor?o do m?sculo mentual para o vedamento labial ap?s a cirurgia. Conclus?o: O vedamento labial ? infuenciado pelo volume ?sseo e/ou gingival e a cirurgia periodontal contribiu para um contato mais suave entre os l?bios
57

Avalia??o da percep??o de periodontistas, protesistas, ortodontistas e leigos sobre par?metros periodontais relacionados ? est?tica do sorriso

Barreto, Alessandra Oliveira 18 March 2009 (has links)
Made available in DSpace on 2014-12-17T15:30:55Z (GMT). No. of bitstreams: 1 AlessandraOB_Dissert.pdf: 1502594 bytes, checksum: b515502c0f4f9f55d34f2aef956d7be8 (MD5) Previous issue date: 2009-03-18 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / The concept of facial esthetics has been increasingly diffused, being of interest to both the general public and the surgeon-dentists. However the difficult standardization and high variability in parameters aesthetic existing in the literature result in a huge difference of opinions between professionals and layperson. In this way, objective of this research was to evaluate the perception of periodontistas, protesistas, orthodontists and layperson about aesthetics smile. The sample included 30 periodontistas, 30 protesistas, 31 orthodontists and 37 layperson. The data collection was performed through an interview indirect, by the site, which had fifteen photos to be assessed by the participants. Each photograph was intentionally modified, with four increments 1mm for each amendment, in the program Adobe Photoshop CS2 version 9.0, adding-four aesthetic alterations: exposure gingival, recession gingival, absence of papilla and contour gingival. The smile for periodontistas, 3mm for orthodontists and laity and 4mm for protesistas. And changes in recession gingival, have undertaken the aesthetics of smiling from 2mm in accordance with the periodontistas and protesistas and 4mm for orthodontists and lay people. The end of the research was possible to conclude that the perception of periodontistas, protesistas, orthodontists and layperson are different in relation to aesthetics smile, and that among the changes in the research evaluated the papilla and recession have undertaken the aesthetics of smile / O conceito da est?tica facial tem sido cada vez mais difundido, sendo de interesse tanto do p?blico geral como dos cirurgi?es-dentistas. No entanto a dif?cil padroniza??o e alta variabilidade dos par?metros est?tico existentes na literatura resultam em uma enorme diferen?a de opini?es entre profissionais da ?rea e leigos. Deste modo, objetivo desta pesquisa foi avaliar a percep??o de periodontistas, protesistas, ortodontistas e leigos sobre a est?tica do sorriso. A amostra envolveu 30 periodontistas, 30 protesistas, 31 ortodontistas e 37 leigos. A coleta dos dados foi realizada atrav?s de entrevista indireta, pelo site, no qual possu?a quinze fotografias para serem avaliadas pelos participantes. Cada fotografia foi intencionalmente modificadas, com quatro incrementos de 1mm para cada altera??o, no programa Adobe Photoshop CS2 vers?o 9.0, acrescentando-se quatro altera??es est?ticas: exposi??o gengival, a recess?o gengival, aus?ncia de papila e contorno gengival. E os resultados demonstraram que a perda de papila, quando alterada em 2mm comprometimento na est?tica do sorriso para os periodontistas, em 3mm para os ortodontistas e leigos e 4mm para os protesistas. E as altera??es na recess?o gengival, comprometeram a est?tica do sorriso a partir de 2mm de acordo com os periodontistas e protesistas e 4mm para os ortodontistas e leigos. Ao final da pesquisa foi poss?vel concluir que a percep??o dos periodontistas, protesistas, ortodontistas e leigos s?o diferentes em rela??o ? est?tica do sorriso, e que dentre as altera??es avaliadas na pesquisa a papila e a recess?o comprometeram a est?tica do sorriso
58

Ontogênse do sorriso no contexto da interação mãe-bebê / Smile's ontogeny in the mother-infant interaction context

Deise Maria Leal Fernandes Mendes 12 March 2008 (has links)
Fundação de Amparo à Pesquisa do Estado do Rio de Janeiro / Esta tese teve como objetivos: (I) propor uma articulação teórica para o estudo do sorriso contemplando a dimensão histórica, sociocultural e evolutiva da espécie humana e seu aparato biológico; (II) realizar dois estudos empíricos, um longitudinal, da terceira semana ao sexto mês de vida de dois bebês e outro transversal, com bebês de um, dois e cinco meses de nascidos, com o propósito de: (II.1) investigar se há algum padrão de sorrisos em termos de freqüência, duração e características morfológicas, e se ocorrem transformações nesse padrão nos seis primeiros meses de vida; (II.2) analisar padrões de sorriso apresentados na presença de comportamentos afetivos da mãe, nesse período; e (II.3) verificar se os bebês respondem de modo contingente, com sorrisos, aos comportamentos afetivos da mãe, e se há padrões diferenciados por tipo de sorriso. Participaram do estudo longitudinal duas díades mãe-bebê, filmadas em suas residências, semanalmente. Do estudo transversal, para cada grupo de diferentes idades, participaram vinte díades mãe-bebê, também filmadas em suas residências. As categorias de observação, comuns aos dois estudos, foram codificadas em duas partes, sendo a referente aos sorrisos do bebê com comportamentos mutuamente exclusivos e exaustivos. Os índices de Kappa de Cohen e de concordância indicaram boa fidedignidade entre os observadores. Entre outras evidências, verificou-se tendência de trajetória de curva ascendente para os sorrisos dos bebês no período estudado, F(1,22) = 6,77, p<0,05, para um dos bebês do estudo longitudinal, e, F(1,23) = 7,85, p<0,05, para o outro. Os dois bebês revelaram uma tendência particular a exibir com mais freqüência um ou dois tipos de sorrisos. Os sorrisos da mãe, como demais comportamentos afetivos, mostraram-se potenciais eliciadores de sorrisos de tipos variados nos bebês. Correlações significativas foram encontradas, na pesquisa longitudinal, entre os tipos mais freqüentes de sorrisos dos bebês e os sorrisos de suas mães (r=0,77, p<0,0017, para um dos bebês, e r=0,62, p<0,0017, para o outro). Também no estudo transversal foi verificada correlação entre o sorriso simples e o sorriso da mãe (r=0,70, p<0,0007). Sorrisos de diferentes tipos foram exibidos pelos bebês, tanto no estudo longitudinal, quanto no transversal, como respostas contingentes aos comportamentos maternos observados. Esses e outros resultados indicam uma associação significativa entre os sorrisos dos bebês e comportamentos afetivos das mães. A relevância da temática desse trabalho contrasta com a carência de estudos brasileiros sobre o tema. Entende-se que essa lacuna precisa ser superada, e esta tese representou um movimento nessa direção. / This doctoral dissertation had the following purposes: (I) to propose an approach to the study of smile that integrates a historical, socio-cultural and evolutionary, and biological dimmension; (II) to carry out two empirical studies, the first one longitudinal, reaching from the third week to the sixth lifes month of two babies, and the second one, a transversal studie, at the first, the second and the fifth months of life, with the proposition of: (II.1) to investigate any eventual standard of smile exibition in terms of frequency, duration and morfological characteristics, and any possible transformation in this standard during the first six months of life; (II.2) to analyze the smile standards observed in the presence of mothers affective behaviors during the first six months of life; and (II.3) to verify if the babies can answer contingently, with smiles, to the mothers affectives behaviors, and also if there are specific standards for each kind of smile. Two mothers and their babies participated in the longitudinal study and were videotaped at home. Twenty mothers and their babies participated, for each of the three groups of different ages in the transversal study, and were videotaped at home. The observation categories in these two studies are codified in two parts. The first part had mutually exclusive and exhaustive behaviors (babys smiles). The Cohens Kappa and the agreement indexes indicated good reliability inter observers. Among the evidences, it was verified a incrising curve trajetorial tendency for the babiess smiles in the period studied, F(1,22) = 6,77, p<0,05 for the first baby, and F(1,23) = 7,85, p<0,05 for the second one, both of them in the longitudinal study context. The two babies have revealed a particular tendency to frequentely display one or two kinds of smile. Babies also answered contingently with smiles to mothers affective behaviors in the two studies. In the longitudinal resourch, correlations between the more frequent kinds of the babies smiles and his mothers smiles were verified (r=0,77, p<0,0017 for one baby, and r=0,62, p<0,0017 for the other). In the transversal research, correlations between the simple smile and the mothers smile were verified (r=0,70, p<0,0007). Differents kinds of smiles have been exibited from the babies, in the both studies, longitudinal and transversal, as contigencial anwers to the mothers observed behaviors. This and others results sinalize to an association between the babies smile and his mothers affective behaviors. The relevance of investigating babiessmile contrats with the lack of Brazilian studies on this theme. This dissertation intended to contributeas an effort to supply this gap.
59

Digital smile design (DSD): influência na percepção e preferência do paciente e do cirurgião-dentista quanto a estética do sorriso no Mock up / Digital smile design (DSD): influence in the perception and preference of the patient and the dental surgeon regarding the aesthetics of the smile on the Mock-up

Vidal, Andréia Prado Cortizo 30 November 2018 (has links)
Submitted by Liliane Ferreira (ljuvencia30@gmail.com) on 2018-11-28T12:11:28Z No. of bitstreams: 2 Dissertação - Andreia Prado Cortizo Vidal - 2018.pdf: 4289900 bytes, checksum: 4269b56ac46c672423d896fec8f70f86 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2018-11-28T13:55:22Z (GMT) No. of bitstreams: 2 Dissertação - Andreia Prado Cortizo Vidal - 2018.pdf: 4289900 bytes, checksum: 4269b56ac46c672423d896fec8f70f86 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2018-11-28T13:55:22Z (GMT). No. of bitstreams: 2 Dissertação - Andreia Prado Cortizo Vidal - 2018.pdf: 4289900 bytes, checksum: 4269b56ac46c672423d896fec8f70f86 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2018-11-30 / Aesthetic perception is a highly subjective concept and the opinion of professionals regarding smile aesthetic evaluation may not meet the perception and expectation of patients and lay people. Tools such as the Digital Smile Design (DSD) allows reproducing to the patient in a more comprehensive way, what was planned by the professional, still in the phases that anticipates the execution of the restorative treatment, such as diagnostic the wax-up and mock-up. However, the result obtained by the DSD may not meet the patient’s expectations, besides being a stage that demands time and training. This work aimed to evaluate whether the use of the DSD influences the making of the diagnostic wax up and the perception and preference of the patient and the dentist on the aesthetics of the smile with mock ups obtained from waxes with and without DSD. The sample consisted of 10 patients recruited from individuals who had interest and need for aesthetic smile treatment and 10 dentists who use the DSD on a regular basis. Initially, two wax-up were performed for each patient, one performed in the traditional way, without the DSD, and another guided by the DSD. Two mock-ups were performed, one for each wax-up. After installation, the following photographs were taken with the mock-up: 1. frontal facial at rest, 2. frontal facial at maximum smile, 3. frontal lip approximation at rest, 4. frontal lip approximation at maximum smile, 5. frontal lip approximation with retractor . The photos were presented to the patients individually, along with a Preference Sheet, where they assigned the alternative regarding the smile that most pleased them: 1. photo without intervention; 2. mock-up photo with DSD; 3. mock-up photo without DSD; 4. none of the above; 5. indifferent. The patients opted on their own photos and the dentists evaluated the photos of each one of the 10 patients. It has been observed that there is a tendency by the patients and dentists to prefer the mock-up without DSD, possibly because it is closer to the natural morphology of the teeth. / A percepção estética é um conceito altamente subjetivo e a opinião de profissionais em relação a avaliação estética do sorriso pode não coincidir com a percepção e expectativa de pacientes e leigos. Ferramentas computacionais como o Digital Smile Design (DSD) permitem apresentar para o paciente de uma maneira mais compreensível o que foi planejado pelo profissional, ainda nas fases que antecipam a execução do tratamento restaurador, como enceramento diagnóstico e mock up. Porém, o resultado obtido com o DSD pode não corresponder às expectativas do paciente, além de ser uma etapa que demanda tempo e treinamento. Este trabalho objetivou avaliar se o uso do DSD influencia na obtenção do enceramento diagnóstico e na percepção e preferência do paciente e do cirurgião-dentista quanto a estética do sorriso com mock ups obtidos a partir de enceramentos com e sem DSD. A amostra foi composta por 10 (dez) pacientes recrutados dentre indivíduos que tinham interesse e necessidade de tratamento estético do sorriso e 10 (dez) cirurgiões-dentistas que fazem uso corriqueiro do DSD. Inicialmente foram realizados dois enceramentos diagnósticos para cada paciente, sendo um obtido de forma tradicional, sem auxílio do DSD, e outro obtido de forma orientada com o DSD. Foram realizados dois mock ups para cada enceramento. Após instalação de cada mock up foram feitas as seguintes fotografias: 1. facial frontal em repouso, 2. facial frontal em sorriso máximo, 3. frontal aproximada dos lábios em repouso, 4. frontal aproximada dos lábios em sorriso máximo e 5. frontal aproximada em máxima intercuspidação habitual (MIH) com afastador. As fotos foram apresentadas aos participantes de forma individual, juntamente com uma Ficha de Preferência, onde assinalaram a alternativa referente ao sorriso que mais os agradou: 1. foto sem intervenção; 2. foto do mock up com DSD; 3. foto do mock up sem DSD; 4. nenhuma das anteriores; 5. indiferente. Os pacientes opinaram em relação a suas próprias fotografias e os cirurgiões-dentistas avaliaram as fotografias de cada um dos 10 pacientes. Observou-se que existe uma tendência por parte dos pacientes e cirurgiões-dentistas em preferir o mock up sem DSD, por este possivelmente se aproximar mais da morfologia natural dos dentes.
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Aplicações da expansão de Edgeworth à precificação de derivativos financeiros / Testing option pricing with the Edgeworth expansion

Ruy Gabriel Balieiro Filho 19 February 2003 (has links)
O Objetivo deste trabalho é usar uma ferramenta matemática conhecida como expansão de Edgeworth em conjunto com a moderna teoria de análise de derivativos financeiros que utilizam o método de precificação neutra ao risco. Tal expansão permite obter uma função densidade de probabilidade com assimetria e curtose arbitrárias a partir de uma densidade normal. Desta forma, podemos usar esta nova distribuição como a state price density do ativo-objeto procurando corrigir o sorriso da volatilidade através da definição de funções de probabilidade com assimetrias positivas ou negativas e curtose maior de que três. Além disso esperamos também chegar a uma nova maneira de realizar o delta hedge de uma carteira de replicação de modo mais eficiente do que a de Black-Scholes. / There is a well-developed framework, the Black?Scholes theory, for the pricing of contracts based on the future prices of certain assets, called options. This theory assumes that the probability distribution of the returns of the underlying asset is a Gaussian distribution. However, it is observed in the market that this hypothesis is 2awed, leading to the introduction of a fudge factor, the so-called volatility smile. Therefore, it would be interesting to explore extensions of the Black?Scholes theory to non-Gaussian distributions. In this paper, we provide an explicit formula for the price of an option when the distributions of the returns of the underlying asset is parametrized by an Edgeworth expansion, which allows for the introduction of higher independent moments of the probability distribution, namely skewness and kurtosis. We test our formula with options in the Brazilian and American markets, showing that the volatility smile can be reduced. We also check whether our approach leads to more e6cient hedging strategies of these instruments.

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