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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.
81

Hodnocení chovu krav bez tržní produkce mléka na ekologické a konvenční farmě / Evaluation of the bred of cows in the system without market milk production at ecological and conventional farm

ROUŠALOVÁ, Miroslava January 2008 (has links)
The aim of work was comparing breeding of suckler cows in agriculture companies with different methods of farming. Both farms are in the same climate conditions in submontaine region in Blanský Les. I included a herd of cows {--} bred Aberdeen Argus from the conventionally company and crossbreeds (the higher blood percentage of race Aberdeen Argus) are at the ecological farm. In both farms was checked same indices (reproduction inbreed, health problems cows and calves, management herd, sustenance, grazing system and economy of breed). Data was assessed behind period two years 2005 and 2006.
82

Impacto da vacinação com a PCV10 na morbidade hospitalar por pneumonia no Brasil: análise de série temporal interrompida / Impact of vaccination with PCV10 in hospital morbidity due to pneumonia in Brazil: interrupted time series analysis

Afonso, Eliane Terezinha 19 August 2015 (has links)
Submitted by Marlene Santos (marlene.bc.ufg@gmail.com) on 2016-04-20T19:18:23Z No. of bitstreams: 2 Tese - Eliane Terezinha Afonso - 2015.pdf: 3480407 bytes, checksum: db146d8884a4aedac166a73ef268d89d (MD5) license_rdf: 19874 bytes, checksum: 38cb62ef53e6f513db2fb7e337df6485 (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2016-04-25T15:00:31Z (GMT) No. of bitstreams: 2 Tese - Eliane Terezinha Afonso - 2015.pdf: 3480407 bytes, checksum: db146d8884a4aedac166a73ef268d89d (MD5) license_rdf: 19874 bytes, checksum: 38cb62ef53e6f513db2fb7e337df6485 (MD5) / Made available in DSpace on 2016-04-25T15:00:31Z (GMT). No. of bitstreams: 2 Tese - Eliane Terezinha Afonso - 2015.pdf: 3480407 bytes, checksum: db146d8884a4aedac166a73ef268d89d (MD5) license_rdf: 19874 bytes, checksum: 38cb62ef53e6f513db2fb7e337df6485 (MD5) Previous issue date: 2015-08-19 / BACKGROUND: Pneumonia causes substantial morbidity and mortality in all age groups around the world. The 10-valent pneumococcal conjugate vaccine (PCV10) was introduced into the routine infant immunization in Brazil, free of charge, in March 2010. The aim of this study was to evaluate the impact PCV10 vaccination on rates of all cause pneumonia hospitalizations one year and three years after its introduction in Brazil. METHODS: We conducted two interrupted time series analysis studies. The first evaluated only the direct effect of PCV10 vaccination, in five Brazilian cities (Belo Horizonte, Curitiba, Porto Alegre, São Paulo and Recife), and was conducted one year after starting the vaccination. The second study evaluated the direct and indirect impact (individuals not vaccinated) of PCV10 vaccination in Brazil, and was conducted three years after vaccination. We used data from the Brazilian Hospitalization System from 2005-2013. The main outcome was monthly rates of all-cause pneumonia hospitalizations identified by ICD-10 codes J12-J18. We used hospitalization rates for congenital malformations and non-respiratory causes as a comparison groups. The time-series analysis was based on a generalized linear model. Pneumonia rates observed in the pre-vaccination period were used to estimate the hospitalization rates in the post-vaccination period of each study, adjusting for seasonality and secular trends. To estimate the direct (2-23 months of age) and indirect (≥5 years of age) impact of PCV10 vaccination, we calculated the percentage change in hospitalization rates, as the observed divided by the predicted rates of hospitalization in the post-intervention period minus one, with respective 95% CI and p values. The number of all-cause pneumonia hospitalizations averted by vaccination was calculated taking into account the difference between the predicted and observed number in the PCV10 post vaccination period. RESULTS: One year after introduction of PCV10 in Brazil, significant declines in hospitalizations for pneumonia in children aged 2-23 months were noted in Belo Horizonte (28.7%), Curitiba (23.3%), and Recife (27.4%). After three years of the introduction of PCV10, 461,519 pneumonia hospitalizations were averted in Brazil, and a significant decrease in rates of pneumonia hospitalization was observed in unvaccinated individuals aged 5-39 years, ranging from 14.1-17.4% (p<0.05). In contrast, an increased trend in pneumonia hospitalizations (p=0·004) was observed for elderly (≥ 65 years). CONCLUSION: Vaccination with PCV10 in Brazil was associated with reduction of pneumonia hospitalizations in vaccinated individuals. Herd effect was observed in individuals aged 5-39 years after three years of vaccination. Potential reasons for the increased trend in pneumonia hospitalization rates in the elderly should be investigated. / INTRODUÇÃO: As pneumonias contribuem com alta carga de morbimortalidades em todo mundo. No Brasil, a vacina pneumocócica conjugada 10 valente (PCV10) foi introduzida na rotina de imunização da infância em março de 2010. Este estudo teve como objetivo avaliar o impacto da vacinação nas taxas de hospitalizações por pneumonia no Brasil no curto e médio prazo do início da vacinação. METODOLOGIA: Dois estudos de séries temporais interrompidas foram conduzidos. O primeiro avaliou o efeito direto da vacinação em cinco capitais brasileiras (Belo Horizonte, Curitiba, Porto Alegre, São Paulo e Recife) e foi conduzido após um ano de introdução da PCV10 no país. O segundo estudo avaliou o impacto direto e indireto (população não vacinada) da vacinação em todo país e foi conduzido três anos após sua introdução. Os dados de hospitalizações foram obtidos do Sistema de Informações Hospitalares (SIH-SUS) de 2005 a 2013. O desfecho principal foi a taxa mensal de hospitalização por pneumonia definida pelos códigos J12-J18 da CID10. As taxas de hospitalizações por malformações congênitas e causas não respiratórias foram utilizadas como grupos de comparações. A análise de série temporal utilizou um modelo de regressão linear generalizado. As taxas de hospitalizações por pneumonia observadas no período pré-PCV10, ajustadas por tendência secular e sazonalidade, foram utilizadas para estimar as taxas no período pós-PCV10. O impacto da vacinação para cada faixa etária foi calculado como o percentual de mudança nas taxas de hospitalizações, dividindo-se as taxas observadas pelas taxas preditas do período pós PCV10, menos um. Os respectivos IC95% e os valores de p foram apresentados. O número de hospitalizações por pneumonia evitadas após três anos de vacinação foi estimado pela diferença entre os números de hospitalizações por pneumonia preditos e observados no período pós-vacinação. RESULTADOS: Após um ano de introdução da PCV10 no Brasil, observou-se significativo declínio nas taxas de hospitalizações por pneumonia em crianças de 2 a 23 meses em três das cinco capitais estudadas: Belo Horizonte (28,7%), Curitiba (23,3%), e Recife (27,4%). Após três anos da introdução da PCV10, 461.519 hospitalizações por pneumonia foram evitadas no Brasil e um significativo declínio nas taxas de pneumonia foi observado em indivíduos não vacinados de 5 a 39 anos variando de 14,1% a 17,4% (p<0,05). No entanto, observou-se um aumento significativo (9,9%, p=0,004) nas taxas de hospitalizações por pneumonia para idosos ≥65 anos. CONCLUSÕES: A vacinação com a PCV10 foi associada à significativa redução das hospitalizações por pneumonia na infância. Adicionalmente, o estudo evidenciou importante redução das hospitalizações por pneumonia em grupos etários não vacinados, sinalizando efeito indireto conferida pela vacina. A tendência de aumento das hospitalizações por pneumonias em idosos necessita de investigações para elucidação dos fatores envolvidos nesse fenômeno.
83

Uso de modelos de análise de decisão nos programas de vacinação contra a varicela / Use of decision analysis models in the programs of vaccination against varicella

Patricia Coelho de Soárez 03 September 2009 (has links)
INTRODUÇÃO: A escolha entre diferentes modelos de análise de decisão introduz variabilidade nos resultados das avaliações econômicas. Modelos estáticos não captam os efeitos indiretos da vacinação comprometendo a avaliação geral dos benefícios da vacinação. Neste trabalho foram desenvolvidos um modelo dinâmico e um modelo estático para a análise de custo-efetividade (ACE) da vacina contra varicela e foram comparados os resultados obtidos com os dois modelos. MÉTODOS: Avaliação econômica completa do tipo ACE usando modelagem. As análises compararam duas estratégias: 1) introdução da vacinação infantil de rotina aos 12 meses de vida; versus 2) situação existente (vacinação após os surtos em creches e vacinação de imunodeprimidos). As análises foram conduzidas no horizonte temporal de 30 anos. RESULTADOS: O modelo dinâmico estimou que na ausência do programa de vacinação ocorreriam 2 915 294 casos de varicela por ano no Brasil, resultando em 879 095 casos ambulatoriais, 4 507 hospitalizações, 119 mortes e 4 casos de sequela. O custo total anual da varicela foi estimado em R$27 378 957 para a sociedade e em R$14 412 610 para o sistema de saúde. A razão de custo-efetividade incremental (RCEI) por ano de vida salvo foi R$14 749 na perspectiva da sociedade e R$16 582 na perspectiva do sistema de saúde. O modelo estático estimou que na ausência do programa de vacinação ocorreriam 1 656 547 casos de varicela por ano no Brasil, resultando em 629 488 casos ambulatoriais, 5 120 hospitalizações, 82 mortes e 1 caso de sequela. O custo total anual da varicela foi estimado em R$17 311 412 para a sociedade e em R$9 570 551 para o sistema de saúde. A RCEI por ano de vida salvo foi R$35 254 na perspectiva da sociedade e R$36 599 na perspectiva do sistema de saúde. Aplicando o limiar de custoefetividade da Organização Mundial de Saúde (OMS) aos resultados obtidos com o modelo dinâmico a vacinação foi considerada uma estratégia custo-efetiva o mesmo não aconteceu com os resultados do modelo estático. Na análise de sensibilidade da taxa de incidência utilizada no modelo estático a RCEI por ano de vida salvo foi R$19 905 na perspectiva da sociedade e R$21 176 na perspectiva do sistema de saúde e a vacinação foi considerada custo-efetiva. CONCLUSÃO: A estimativa de custo-efetividade de programas de vacinação exige o uso de um modelo apropriado. O que é julgado como apropriado será influenciado pelo contexto da avaliação proposta, conhecimento da epidemiologia da doença, disponibilidade de dados e existência de uma equipe qualificada para construir e interpretar os resultados desses modelos. / BACKGROUND: The choice between different decision analysis models introduces variability in the results of economic evaluations. Static models do not take into account the indirect effects of vaccination, thus compromising the overall assessment of vaccination benefits. This work developed two models one dynamic and another static to conduct cost-effectiveness analyses (CEA) of varicella vaccine, comparing the results of the two. METHODS: Comprehensive economic evaluation CEA using modeling. The analysis compared two strategies: 1) introduction of routine vaccination for children under 12 months, versus 2) current situation (vaccination after outbreaks in nurseries and vaccination of immunocompromised). The time horizon of the analysis was 30 years. RESULTS: The dynamic model estimated that in the absence of the vaccination program, 2 915 294 cases of varicella occurred every year in Brazil, resulting in 879,095 outpatient cases, 4,507 hospitalizations, 119 deaths and 4 sequela cases. The total annual cost of varicella was estimated at R$ 27,378,957 for the society and at R$ 14,412,610 for the health care system. From the perspective of society, the incremental cost-effectiveness ratio (ICER) was R$ 14,749 per life-year saved, while from the perspective of the health care system, it amounted to R$ 16,582. The model estimated that, in the absence of a vaccination program, there would be 1,656,547 cases of varicella every year in Brazil, resulting in 629,488 outpatient cases, 5,120 hospitalizations, 82 deaths and 1 case of sequela. The total annual cost of varicella was estimated at R$ 17,311,412 for the society, and at R$ 9,570,551 for the health care system. The ICER was R$ 35,254 and R$ 36,599 from the perspective of society and the health care system, respectively. When applying the World Health Organization (WHO)\'s cost-effectiveness threshold to the dynamic model results, vaccination was considered a cost-effective strategy; this was nevertheless not the case with the static model. In the sensitivity analysis for the incidence rate employed in the static model, the ICER was R$ 19,905 per life-year saved from the perspective of society, and R$ 21,176 from the perspective of the health care system, with vaccination deemed cost-effective. CONCLUSION: Estimating the cost-effectiveness of vaccination programs requires the use of an appropriate model. Establishing an appropriate course of action will depend on the context of proposal evaluation, understanding of disease epidemiology, availability of data, and the existence of a qualified team to build these models and interpret their results.
84

Perfil eletroforético das proteínas do leite e estabilidade no teste do álcool. / Electrophoretic profile of milk proteins and stability in alcohol test

Barbosa, Rosângela Silveira 30 June 2011 (has links)
Made available in DSpace on 2014-08-20T14:38:44Z (GMT). No. of bitstreams: 1 Tese_Rosangela_Barbosa.pdf: 1566771 bytes, checksum: 708102103c93f84a79e40209c65341e8 (MD5) Previous issue date: 2011-06-30 / Unstable non acid milk (LINA) characterizes for lack of stability of caseins, resulting in coagulation in the alcohol test, without high acidity, above 18°D and with changes in the milk s physic and chemical properties. Among chemical attributes, differences of total crude protein and protein fractions percentages are noticeable between stable and unstable milk. This study aimed to evaluate the relation between milk s electrophoretic profile and stability in the alcohol test with cows being fed with different diets. The trials were conducted at the dairy region of Pelotas, at the south of Rio Grande do sul State, Brazil.The first trial was held at the Embrapa Clima Temperado, from April to August, with two diets: control and feeding restriction, 100 and 60% of previous feeding amounts, with six Jersey cows, at the beginning of their lactation. The second trial was held at the Embrapa Clima Temperado, from May to June, with three diets: control (no additive inclusion), addition of sodium bicarbonate and addition of sodium citrate, with 17 Jersey cows at all lactation stages (76 to 293 days in milking). The third trial was held at the Colégio Agrícola Visconde da Graça UFPEL, from march to April, with three diets: control (deficient), 100% of energy nutritional requirements and 100% of protein-energy nutritional requirements, using 12 Holstein and Jersey cows, at the beginning and mid lactation. In all evaluations the following analyses were performed: alcohol test (with ethanol concentration from 68 to 80°GL v/v), titrable acidity, pH, boiling test, chemical composition, Somatic Cells Count (SCC). Besides, milk production, body weight, body condition score were 12 also evaluated. Milk s protein fractions were evaluate with electrophoreses in 12% poliacrilamide gel. In the first trial, diets did not change protein fraction of the milk not its composition and stability, just milk production. However, stable milk and unstable milk presented differences for κ-CN percentages. In the second, the addition of sodium bicarbonate and addition of sodium citrate, influenced protein fraction β e κ-CN. The unstable milk presented higher amounts of αs-CN. In the third, the adjusted diets could alter milk production, protein, total solids and levels of calcium in milk and blood. / O Leite Instável Não Ácido (LINA) caracteriza-se pela perda da estabilidade das caseínas, resultando em precipitação positiva ao teste do álcool, sem apresentar acidez elevada acima de 18ºD e com alterações nas suas propriedades físico-químicas. Dentre as propriedades químicas destaca-se a diferença na porcentagem de proteína total e das frações protéicas entre leite estável e aquele instável no teste do álcool. O objetivo foi avaliar a relação entre o perfil eletroforético das frações protéicas do leite e sua estabilidade no teste do álcool com vacas recebendo diferentes dietas. Os experimentos foram conduzidos na bacia leiteira de Pelotas, zona sul do Rio Grande do Sul Brasil. O primeiro foi realizado na Embrapa Clima Temperado, nas estações de outono e inverno (de abril a agosto), com dois tratamentos: controle (dieta equilibrada) e restrição alimentar (60% de fornecimento de alimento), em seis vacas em lactação da raça Jersey, no estágio inicial de lactação. O segundo experimento foi realizado na Embrapa Clima Temperado, na estação do outono (maio a junho), com três tratamentos: controle (atendendo 100% das exigências nutricionais), adição de bicarbonato de sódio e adição de citrato de sódio, usando 17 vacas da raça Jersey, com média de 30 semanas de lactação). O terceiro experimento foi realizado no Colégio Agrícola Visconde da Graça UFPel, 10 nas estações: final de verão e início do outono (março a abril), com 3 tratamentos: controle (sem atender as necessidades nutricionais dos animais), 100% de atendimento das exigências energéticas e 100% de atendimento das exigências energético-protéicas, usando 12 vacas da raças Jersey e Holandês, no primeiro e segundo estádio de lactação. Em todas as etapas foram realizadas as análises: teste do álcool (68 a 80ºGL v/v, acidez titulável, pH, fervura, composição química (gordura, proteína, lactose, sólidos totais), contagem de células somáticas. Foram avaliados os parâmetros de produção de leite, peso corporal, escore da condição corporal. Além dessas, foi realizado eletroforese em gel de poliacrilamida 15% para determinação das frações protéicas do leite. No primeiro experimento, conclui-se que as dietas não alteraram as frações protéicas, composição e estabilidade do leite e parâmetros produtivos das vacas em estudo, com exceção da produção de leite. Já com relação a comparação de leite estável e leite instável no teste do álcool houve diferenças na fração protéica β-caseína. O grupo de vacas com menor estabilidade do leite apresentou menor proporção de β, mas maior de k-CN, caseína total e proporção de caseína. No segundo experimento, os aditivos bicarbonato de sódio e citrato de sódio influenciaram apenas as frações protéicas β e κ-caseína. O leite instável apresentou maiores quantidades de αs-caseína. No terceiro experimento, as dietas ajustadas foram suficientes para reverter o quadro de LINA, causar influência na produção do leite, proteína, sólidos totais e teor de cálcio no leite e sangue.
85

Vers des systèmes d'élevage résilients : une approche de l'allocation de la ressource pour combiner sélection et conduite dans l'environnement du troupeau / Towards resilient livestock systems : a resource allocation approach to combine selection and management within the herd environment

Douhard, Frédéric 05 November 2013 (has links)
Sélectionner les animaux qui ont le plus haut niveau de production, en tenant peu compte d’autres caractères, a toujours bien fonctionné dans les conditions d’un environnement favorable (i.e. ration riche en nutriments, faible charge pathogène, thermoneutralité). Toutefois, pour de nombreuses raisons (économiques, climatiques, écologiques), les éleveurs auront sans doute de plus en plus de mal à réunir de telles conditions dans l’environnement de leur troupeau, et pourront même délibérément choisir de ne pas le faire. Sélectionner des animaux qui soient adaptés avec les conditions futures des troupeaux devient donc tout aussi important qu’adapter la conduite du troupeau en fonction des génotypes sélectionnés. Pour mieux identifier les contraintes et les opportunités d'appliquer ces deux options, nous proposons, pour la première fois dans cette thèse, un modèle animal intégrant les effets de la sélection génétique et de la conduite du troupeau. Ce modèle intègre des coefficients d’allocation de la ressource alimentaire entre les fonctions biologiques en tant que caractères héritables Il permet de simuler à court-terme les performances zootechniques et à long-terme les réponses à la sélection résultant de la transmission de ces caractères d’allocation entre générations. Le modèle a été appliqué à la chèvre laitière et se focalise sur la conduite en lactation longue (LL) d’une partie des chèvres du troupeau (conduite consistant à préserver des femelles en lactation ayant après une mise bas sans réengagement d’une nouvelle reproduction). Nous sommes partis du principe que la sélection et la conduite du troupeau influencent tous deux la façon dont chaque animal alloue ses ressources entre ses fonctions biologiques. Nous avons cherché à évaluer la portée de ce principe pour mieux comprendre le développement des interactions génotype-environnement (G x E) sur le long terme. Dans un troupeau soumis à des variations du niveau d'alimentation, différentes stratégies de sélection ciblant l’amélioration de la production laitière et de la longévité ont été simulées. En accord avec la théorie de l’allocation, les réponses à la sélection révèlent que l’amélioration de la production et de la survie doit faire face à un compromis entre ces deux caractères. Cependant, ce compromis est atténué lorsque la sélection est combinée avec la conduite en LL d’une partie du troupeau. Un tel effet de synergie entre sélection et conduite résulte d’une interaction complexe entre la dynamique individuelle de performance au cours de la LL et le renouvellement du troupeau. Ainsi, la capacité innée des chèvres à prolonger leur lactation semble pouvoir être valorisée pour améliorer la résilience du troupeau. / Selecting those animals that have the greatest level of production, with little regard for other traits, has historically worked well in a favorable environment (i.e. nutrient-rich diet, low pathogen load, thermo-neutrality). However, for numerous reasons (economic, climatic, ecological) farmers will find it increasingly difficult, and indeed may actively choose not, to provide such favorable conditions in their herd environment. Selecting animals that match the future herd environments thus becomes as important as managing the herd environment to match the selected genotypes. To better identify constraints and opportunities to apply these two options, we propose, for the first time, in this thesis an animal model integrating the effects of selection and management. This model integrates resource allocation between life-functions resource as heritable traits. It enables simulating short-term performance and long-term selection response resulting from the transmission of allocation traits between generations. The model was applied to the dairy goat and focused on the management of extended lactation (EL) for a part of the herd (management practice based on keeping females in lactation without a new reproductive cycle). Both selection and management were assumed to influence the way every animal allocates its resource between functions. We aimed to assess the significance of this assumption for a better understanding of the development of genotype-environment interactions (G × E) over the long-term. In a herd subject to variations in the feeding level, different selection strategies aiming at improving milk production and longevity were simulated. In agreement with the resource allocation theory, the selection responses show improving production and survival has to face a trade-off between these two traits. However, this trade-off is alleviated when selection is combined with some proportion of EL in the herd. Such a synergistic effect between selection and management results from a complex interaction between the individual dynamic performance during EL and the herd turnover. Thereby, the innate capacity of goats to extend their lactation might be promoted to enhance herd resilience.
86

Finansiell rådgivning i den postmoderna samtiden

Dahlqvist, Emil, Engberg, Matilda January 2021 (has links)
Avsikten med denna studie har varit att studera det nya fenomenet börsinfluencers och deras samexistens med professionella licensierade rådgivare samt beskriva på vilket sätt betydelsen av den finansiella rådgivarrollen kan ha förändrats, något som inte har behandlats av tidigare forskning. Studiens genomförande utgår från det teoretiska ramverkets nyckelbegrepp Det klassiska ekonomiska finansparadigmet, beteendevetenskaplig finans, den rationella investeraren, den irrationella investeraren, egna fundamentala analyser, flockbeteende &amp; tillgänglighetsheuristik, professionella rådgivare, börsinfluencers och postmodernism som tillsammans bildar analysmodellen. Modellen visar på hur de två rådgivningstrenderna samexisterar och den är indelad i två delar, en “rationell” sida och en “irrationell” sida för att slutligen visa att existensen av båda sidorna tillåts i det postmoderna samhället. Denna studie hade ett postmodernistiskt synsätt vilket medförde att resultatet endast ska betraktas som en av flera versioner av den yttre verkligheten. För att på bästa möjliga sätt kunna uppfylla syftet och besvara frågeställningarna användes dels en innehållsanalys av en dokumentstudie och dels en tematisk analys av sex semistrukturerade intervjuer där kriteriet vid urval av respondenter var att ha ett intresse för aktiemarknaden samt följa minst en börsinfluencer på Instagram. Studien använde dessa två olika metoder för att både kunna beskriva börsinfluencers agerande på sociala plattformar samt för att kunna analysera deras följares uppfattningar och upplevelser av fenomenet. Studien visade att börsinfluencers fyller olika behov hos respondenterna, där vissa ser på fenomenet som en typ av rådgivare vars åsikter och indirekta råd värderas högt vid investeringsbeslut medan andra vänder sig till börsinfluencers för inspiration i sin investeringsprocess. De tidigare tydliga gränsdragningarna och definitionerna av vad en finansiell rådgivare är har luckrats upp och istället lämnat plats för börsinfluencers, fenomenet kan betraktas som produkten av individers pragmatiska behov av lättillgänglig finansiell rådgivning. Där resultatet är börsinfluencers, den hyperrealistiska rådgivaren. / The purpose of this study has been to examine the new phenomenon of stock market influencers and their coexistence with professionally licensed advisers and to describe in what way the significance of the financial adviser role may have changed, something that has not been addressed by previous research. The implementation of the study is based on the theoretical framework's key concepts The classic economic finance paradigm, behavioral finance, the rational investor, the irrational investor, own fundamental analyzes, herd behavior &amp; accessibility heuristics, professional advisors, stock market influencers and postmodernism that together form the analysis model. The model shows how the two advisory trends coexist and it is divided into two parts, one “rational” side and one “irrational” side, to finally show that the existence of both sides is allowed in the postmodern society. This study had a postmodernist approach, which meant that the result should only be considered as one of several versions of the external reality. In order to best fulfill the purpose and answer the questions, a content analysis of a document study and a thematic analysis of six semi-structured interviews were used, where the criterion when selecting respondents was to have an interest in the stock market and follow at least one stock market influencer on Instagram. The study used these two different methods to both be able to describe the actions of stock market influencers on social platforms and to be able to analyze their followers' perceptions and experiences of the phenomenon. The study showed that stock market influencers meet different needs of the respondents, where some see the phenomenon as a type of advisor whose opinions and indirect advice are highly valued in investment decisions while others use stock market influencers for inspiration in their investment process. The previously clear boundaries and definitions of what a financial adviser is have loosened up and instead left room for stock market influencers, the phenomenon can be considered as the product of individuals' pragmatic need for easily accessible financial advice. Where the result is stock market influencers, the hyperrealistic advisor.
87

Characteristics of Stocks and Individual Investor Herd Behavior: A Causal-Comparative Study

Wong, Tze Sun 01 January 2018 (has links)
Some individual investors follow institutional investors in trading, a phenomenon called herding, that leads to excess market volatility and mispriced stocks. Individual investors who herded suffered from inferior investment performances and monetary losses, and the impact is broader in an individual investor dominant market such as Taiwan. Behavioral finance is the theoretical base of herd behavior. The purpose of this causal-comparative study was to examine individual investor herd behavior as related to characteristics of stocks in the Taiwan stock market. The research questions addressed what differences in individual investor herd behavior, if any, existed by market capitalization, price-to-book (P/B) ratio, and industry affiliation. The target population was the individual investors who traded in Taiwan Stock Exchange (TWSE) between January and December 2016. Participants were a purposive sampling of the target population with the exclusions of individual investors who traded illiquid stocks or exchange sanctioned stocks only. Data were collected through a subscription of TWSE data. The extent of individual herding estimated with Lakonishok, Shleifer, and Vishny's measure was 0.04. The 3 characteristics of stocks were separately and as a whole related to individual herding. The findings confirmed more serious sell-herding than buy-herding. The result from the logistic regression extended the knowledge of more serious herding in low P/B ratio stock with other variables controlled and different extents of herding by industry affiliation. The findings may improve individual investor financial literacy that may result in the positive social change of the alleviation of both herding and inferior investment performance.
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The Magic Formula Investing : Att systematiskt överavkasta marknaden? / The Magic Formula Investing

George Göranzon, Emil, Hellqvist, Alexander January 2022 (has links)
Bakgrund: Värdestrategier har historiskt sett ofta genererat överavkastning relativt index. Huruvida en värdestrategi lyckas eller ej återspeglas i dess förmåga att identifiera och utnyttja felprissättningar på aktiemarknaden. Å andra sidan menar den effektiva marknadshypotesen att investeringsstrategier inte kan överavkasta marknaden via strategin i sig, utan att eventuell överavkastning beror på slumpen. Av dessa anledningar blir det intressant att analysera huruvida Greenblatts (2010) The Magic Formula kan generera överavkastning gentemot marknaden. Dessutom blir det intressant att testa om en modifierad strategi har en högre sannolikhet att lyckas med detta.  Syfte: Syftet med denna studie är att analysera huruvida The Magic Formula-strategin, och en modifierad The Magic Formula-strategi kan överavkasta den svenska aktiemarknaden över tid.  Metod: Studien har en kvantitativ strategi med en deduktiv ansats och en longitudinell design. Historiska aktiekurser har hämtats för att testa strategierna, där två fiktiva portföljer har skapats. Resultatet av dessa portföljers prestation har sedan analyserats samt testats statistiskt.  Slutsats: Resultatet visade att The Magic Formula mellan 2011–2022 inte lyckades överavkasta index. En modifierad variant av The Magic Formula lyckades dock överavkasta index avsevärt. Skillnaderna i medelavkastning gick dock inte att säkerställa statistiskt, vilket betyder att den genererade över- och underavkastningen mycket möjligt kan ha varit slumpmässig.  Nyckelord: The Magic Formula, EMH, Aktiv portföljförvaltning, Värdeinvestering, Overconfidence, Riskuppfattning, Flockbeteende / Background: Value investing has historically often generated excess returns relative to index. Whether a value strategy succeeds is reflected in its ability to identify and exploit mispricings in the stock market. On the other hand, the effective market hypothesis indicates that investment strategies cannot overperform the market via the strategy by itself, but that any excess return is random. For these reasons, it would be interesting to analyze whether Greenblatt's (2010) The Magic Formula can generate excess returns relative to the market. In addition, it would be interesting to test whether a modified strategy has a higher probability of succeeding.  Purpose: The purpose of this study is to analyze whether The Magic Formula strategy, and a modified The Magic Formula strategy can outperform the Swedish stock market over time.  Method: The study has a quantitative strategy with a deductive approach and a longitudinal design. Historical stock quotes have been obtained to test the strategies, where two fictitious portfolios have been created. The result of these portfolios' performance has then been analyzed and statistically tested.  Conclusion: The results showed that The Magic Formula between 2011–2022 failed in overperforming the market. However, a modified version of The Magic Formula managed to outperform the index considerably. Though, the differences in average returns could not be ensured statistically, which means that the generated over- and underperformance may very well have been random.  Keywords: The Magic Formula, EMH, Active portfolio management, Value investing, Overconfidence, Risk perception, Herd behaviour
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[pt] HOUVE EFEITO MANADA NO MERCADO DE AÇÕES BRASILEIRO ENTRE 2010 E 2015: UMA ANÁLISE A PARTIR DO MODELO DE CCK / [en] THERE WERE HERDING IN THE BRAZILIAN STOCK MARKET BETWEEN 2010 AND 2015?: AN ANALYSIS FROM THE PERSPECTIVE CCK MODEL

IURI MAJEROWICZ 30 April 2021 (has links)
[pt] O objetivo desse trabalho é observar, com base no modelo de Chang, Cheng e Khorana (2000), se há indícios de que houve efeito manada no mercado de ações brasileiro no período que compreende entre 2010 e 2015. Esse período é marcado por forte instabilidade política e econômica do Brasil e pode-se notar uma grande volatilidade no índice Bovespa. Essa dissertação de mestrado tem por objetivo avaliar, sob os aspectos de finanças comportamentais, se há ou não indícios de que houve algum movimento de efeito manado em um período recente no mercado de ações brasileiro. Outros estudos já testaram o modelo de Cheng et. Al em outros mercados e no próprio mercado brasileiro em períodos diferentes. Após a análise dos resultados do modelo no período citado, não foi possível encontrar indícios de efeito manada no mercado brasileiro. / [en] The aim of this study is to observe, based on the model of Chang, Cheng and Khorana (2000), if there is evidence that there were herding in the Brazilian stock market in the period that goes from 2010 to 2015. This period was marked by a strong political and economic instability and it is possible to notice a great volatility in the Bovespa index. This dissertation aims at evaluating, under the behavioral finance aspects, whether or not there is any indication that there has been any movement of herding in a recent period in the Brazilian stock market. Other studies have already tested the model of Cheng et. Al in other markets and in the Brazilian market itself in different periods. After analyzing the results of the model in the mentioned period, it was not possible to find evidence of a herd behavior in the Brazilian market.
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Energy-saving biomass stove: Short communication

Hoang, Tri 09 December 2015 (has links)
This paper introduces an energy-saving biomass stove. The principle of energy-saving biomass stove is gasification. It is a chemical process, transforms solid fuel into a gas mixture, called (CO + H2 + CH4) gas. Emission lines in the stove chimneys typically remain high temperatures around 900 to 1200C. The composition of the flue gas consists of combustion products of rice husk which are mainly CO2, CO, N2. A little volatile in the rice husk, which could not burn completely, residual oxygen and dust will fly in airflow. The amount of dust in the outlet gas is a combination of unburnt amount of impurity and firewood, usually occupied impurity rate of 1 % by weight of dry husk. Outlet dust of rice husk furnace has a normal size from 500μm to 0.1 micron and a particle concentration ranges from 200-500 mg/m3. Gas emissions is created when using energy-saving stove and they will be used as the main raw material in combustion process Therefore the CO2 emission into the environment when using the stove will be reduced up to 95% of a commonly used stove. / Bài báo giới thiệu một bếp tiết kiệm dùng năng lượng sinh khối. Bếp tiết kiệm năng lượng thực hiện nguyên lý khí hóa sinh khối. Đó là một quá trình hóa học, chuyển hóa các loại nhiên liệu dạng rắn thành một dạng hỗn hợp khí đốt, gọi là khí Gas (CO + H2 + CH4). Dòng khí thải ra ở ống khói của bếp thông thường có nhiệt độ vẫn còn cao khoảng 900 ~ 1200C. Thành phần của khói thải bao gồm các sản phẩm cháy của trấu, chủ yếu là các khí CO2, CO, N2, một ít các chất bốc trong trấu không kịp cháy hết, oxy dư và tro bụi bay theo dòng khí. Lượng bụi tro có trong khói thải chính là một phần của lượng không cháy hết và lượng tạp chất không cháy có trong củi, lượng tạp chất này thường chiếm tỷ lệ 1% trọng lượng trấu khô.Bụi trong khói thải lò đốt trấu thông thường có kích thước hạt từ 500μm tới 0,1μm, nồng độ dao động trong khoảng từ 200-500 mg/m3. Lượng khí thải được sinh ra khi sử dụng bếp tiết kiệm năng lượng, sẽ được dùng làm nguyên liệu đốt cháy chính của quá trình đó. Do đó lượng khí CO2 thải ra môi trường khi sử dụng bếp tiết kiệm sẽ được giảm xuống 95 % so với sử dụng bếp thường.

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