Novas Abordagens para o Uso das Ferramentas Clássicas de Planejamento de Cenários

The future is to be built – is multiple and uncertain. Within the social sciences, scenarios can be defined as a description of a future situation and a course of events that allow move from a primary position toward this future situation. Currently, there is a multiplicity of methods and tools available for building scenarios, including methods of an essentially rationalist approach, as Michel Godet’s method. The purpose of this work is to use the hypothetical-deductive method to reduce, starting from Michel Godet’s Scenario Method and its tools, the complexity of the scenario-building process while maintaining the robustness of the findings. For this purpose, it is proposed two different approaches: (1) to integrate, in one step, the structural analysis and the cross-impact matrix so the first one derives automatically while filling the last one; (2) to use the concept of Bayesian networks as a method to integrate the cross-impact matrix and the morphological analysis. Both approaches aim to reduce the amount of information needed to feed the tools and improve the feedback criteria, resulting in greater flexibility during the process and better holistic view of the system. Scientifically, these approaches open a new field of studies in scenario planning as it appropriates the concept of Bayesian networks, widely used in other areas of knowledge (artificial intelligence, geological studies, medical diagnostics, pattern classification, etc.), and bring it to the field of social sciences.O futuro está para ser construído – é múltiplo e incerto. Dentro das ciências sociais, cenários podem ser definidos como descrição de uma situação futura e de um curso de eventos que permita o movimento de uma posição original para essa situação futura. Atualmente, existe à disposição uma enormidade de métodos e ferramentas para construção de cenários, entre eles métodos de abordagem essencialmente racionalista, como o de Michel Godet. A proposta deste trabalho é utilizar o método hipotético-dedutivo para reduzir, a partir do Método de Cenários de Michel Godet e de suas ferramentas, a complexidade no processo de construção de cenários, mas ao mesmo tempo manter a robustez das conclusões. Para isso, foram propostas duas abordagens: (1) integrar em apenas uma etapa a análise estrutural e a análise de impactos cruzados, a primeira resultando automaticamente do preenchimento da última; (2) utilizar o conceito de redes bayesianas como forma de integrar a matriz de impactos cruzados e a análise morfológica. Ambas as abordagens visam reduzir a quantidade de informações necessárias para alimentar as ferramentas e melhoram o critério de feedback, resultando em maior agilidade no processo e melhor visão holística do sistema. Cientificamente, essas abordagens abrem um novo campo para estudos de planejamento de cenários já que se apropriam do conceito de redes bayesianas, muito utilizado em outras áreas do conhecimento (inteligência artificial, estudos geológicos, diagnósticos médicos, classificação de padrões, etc.) e o trazem para o campo das ciências sociais

Modeling regional supply responses using farm-level economic data and a biophysical model: a case study on Brazilian land-use change

Estimating farmers’ supply responses to changes in framework conditions is important to inform decision-makers on the expected impacts on production volume as well as the resulting land-use shifts. Existing agricultural supply response models generally require either larger databases with farm-level data for microregional analysis or are implemented with a coarse resolution (e.g., country level) due to the lack of data. While such approaches are suitable for regions with abundancy of data or for global-scale analysis, there is a need for an alternative for micro-level analysis in countries with low data availability. In addition, it is important to include the spatial component in the regional supply response analysis, allowing not only the quantification of the overall change in output but also the likely spatial land-use change. Against this background, this dissertation aims to answer the research question whether a combination of a biophysical model with farm-level economic data can be used to estimate farm-level profitability of individual crops and respective cropping systems and thereby simulate farmers’ supply responses in countries with limited data availability. To answer this question, a new modeling approach called Profitability Assessment Model (PAM) is developed, tested and validated. This new modeling approach follows the principles of minimum data, focusing on delivering timely and quantitative analyses with satisfactory accuracy to inform decision-makers. That is an important feature since the overall goal of the concept is to limit the data required by the model to a minimum, allowing quick implementation while accepting moderate accuracy. The PAM is a spatially explicit model with simulation units’ size of spatial resolution grid varying between 5 and 30 arcmin (10x10 to 50x50 km in area), following that used by the Global Biosphere Management Model (GLOBIOM). PAM estimates the profitability of each farming alternative at the simulation unit level and allocates the land to maximize farmers’ return to land. The PAM model is developed and calibrated for the Brazilian agricultural sector. Using Brazil as the case study is interesting due to its overall importance in the global production of agricultural commodities as well as the environmental impact of land-use changes. For this case study, four production system are represented in the PAM model: (a) double cropping of soybeans and maize, (b) soybeans with a cover crop, (c) sugarcane monoculture and (d) beef production. While the profitability of the arable crops is endogenously estimated, beef is considered as an opt-out option, which is modeled based on exogenous return-to-land information. Since soybean, maize and sugarcane production accounts for 84% of the total seeded area in Brazil, the current version of the PAM model represents the most important cropping alternatives to farmers in Brazil, but not all. An important methodological contribution of the dissertation is the development of routines for the extrapolation of each production cost component from the known typical farms’ data to all regions in the country. These routines are based on local expertise as well as existing information on yield levels, prevailing production systems and farming conditions. Each cost component is analyzed individually and, based on theoretical discussions, specific cost functions are proposed following the expected behavior of each cost item – e.g., linear relationship with yields or fixed per ha. That should improve the accuracy of the model in estimating production costs (and finally profitability) while also allowing the model to be adapted to simulate changes in framework conditions that may affect only selected cost items (e.g., a significant increase in fuel prices). In addition, the PAM model improves on existing models because it accounts for specific cost components such as the transport of sugarcane from farm to mill, which is required due to the perishability of the crop. Besides the important impact of inbound transport cost on the overall profitability of sugarcane production, the endogenous simulation of this cost item allows the model to spatially differentiate among regions depending on the current availability of mills. A major constraint for regional profitability analysis is the lack of information regarding farm input and output prices. To overcome this problem, the PAM model provides an interesting alternative by endogenously estimating prices via the transport module. By considering the different transportation costs of each crop and basing the distance estimation on the actual availability of roads, the model allows a straightforward conversion of reference prices to farm-gate prices. The ability to endogenously simulate transport cost is a useful feature for the simulation of scenarios based on price shocks. Apart from the development of the modeling approach, this dissertation focuses on the quantitative model validation as a key step to identify strengths and limitations of the concept. Projected yields are validated against regional statistics and production cost estimates are benchmarked against the two available datasets, with a suitable number of primary typical-farm data. Furthermore, the resulting land-use maps are evaluated against two simplified validation maps representing current land use. In the business-as-usual scenario, the PAM model estimates a national weighted average of returns to land of 248 USD/ha for double cropping and 188 USD/ha for sugarcane. This relationship, however, is different in the states of Sao Paulo and Minas Gerais, where, on average, sugarcane has a higher return to land than double cropping. Benchmarking PAM’s production cost estimates with observed local data shows a satisfactory model accuracy with a relative mean absolute error (rMAE) lower than 14%. The lowest error found in the production cost estimation is in sugarcane (rMAE of 8.7%) and the highest in second-crop maize (rMAE of 14%). The validation of the business-as-usual land-use map shows that the PAM model is able to satisfactorily reproduce the current land use in Brazil. The visual and quantitative validation results show a strong correlation between the available land-use maps, with PAM allocating the same crop as observed in 86% of total arable land. To test the ability of the PAM model to predict land-use and output changes due to changing framework conditions, a scenario analysis is carried out: What will happen in case yields of key crops change significantly as a consequence of climate change? Due to the strong reduction in the returns to land for grains (i.e., maize and soybeans) in the tropical region more than 24% of the current arable land is simulated to move from grains to sugarcane production. These results, however, vary significantly in the different regions, where the most affected states are Goiás, Paraná and Mato Grosso, jointly accounting for more than 55% of the total land-use change. This dissertation contributes to the overall development of regional farmers’ supply response models for countries with limited data availability, showing that it is feasible to combine a biophysical model and farm-level economic data as the basis for the profitability estimation in a high spatial resolution. The ability to estimate individual cost components separately gives the model the required flexibility for the simulation of market- and policy-related questions, providing timely and accurate information for decision-makers. The bottom-up approach based on local expertise is an important strength of the PAM model, avoiding unrealistic parametrization and ensuring that the majority of local features of production systems are included in the estimation. Finally, considering the overall goal of using minimum data, the model accuracy indicates a strong potential of the model to answer research questions, with additional parametrization and integration expected to further improve its performance.2021-11-1

Influência do padrão de sono sobre o ganho de peso ao longo da gestação

Background: Excessive weight gain during pregnancy has been associated with adverse outcomes to perinatal health, as well as low sleep quality, which is frequently reported during pregnancy. Objective: Therefore, the focus of this study was to evaluate the associations between sleep patterns – time and quality – and the increase in weight during pregnancy. Methods: A prospective and longitudinal study was conducted with 63 pregnant women attending antenatal clinics of the public health service of the city of Uberlandia, Minas Gerais State, Brazil. Pregnant women were evaluated at the first, second and third trimester for subjective sleep patterns [duration and quality determined by Pittsburgh Sleep Quality Index (PSQI)] and anthropometric variables (weight and height, for body mass index (BMI). Generalized estimating equations (GEE) were used to examine the association between sleep duration, quality, and BMI over the pregnancy period, while adjusting for confounders (age, physical activity and energy intake). Results: In the GEE analysis, an effect of interaction between time of pregnancy and clusters of sleep quality was observed on the BMI (p 10) e a ingestão calórica usual. Resultados: Na análise do GEE, foi observada uma interação do efeito do tempo da gestação e clusters de qualidade do sono sobre o IMC (p < 0,05), indicando que gestantes com melhor padrão de sono ganham mais peso do segundo para o terceiro trimestre gestacional, enquanto que aquelas com pior padrão de sono ganham mais peso do primeiro para o segundo. A análise do GEE não encontrou efeito do tempo de sono sobre o ganho de peso. Contudo, foi encontrado que gestantes que mantiveram-se na mesma faixa de peso durante a gestação aumentaram o tempo de sono do primeiro para o terceiro trimestre, enquanto que gestantes que ascenderam a faixa de peso dormiram o mesmo tempo nesse período (mediana = 1,0 [0,0 – 2,0] e mediana = 0,0 [-2,0 – 1,0], respectivamente, p=0,039). Conclusão: A pior qualidade do sono parece levar a uma inadequada distribuição do ganho de peso durante a gestação. Estudos futuros que confirmem tais achados podem auxiliar na elaboração de estratégias voltadas à melhoria da saúde das gestantes

Testing Option Pricing with the Edgeworth Expansion

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 flawed, 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 contribution 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 efficient hedging strategies of these instruments.Comment: 9 pages, 3 figure. Contribution to the International Workshop on Trends and Perspectives on Extensive and Non-Extensive Statistical Mechanics, November 19-21, 2003, Angra dos Reis, Brazi

GESTÃO PARTICIPATIVA DEMOCRÁTICA: IMPASSES, CONQUISTAS E DESAFIOS

A Gestão Pública Democrática refere-se ao processo de participação e controle social por parte da sociedade civil na condução da administração pública e, traduz-se em uma conquista histórica no cenário brasileiro. Coloca-se que a Gestão Participativa Democrática é assegurada legalmente, todavia, questiona-se sua real materialização. Dessa forma, o presente trabalho visou analisar o processo de efetivação da condução democrática da gestão pública municipal. Tratou-se de um estudo descritivo e de caráter qualitativo, que fez uso de pesquisa bibliográfica e documental, cujo lócus de pesquisa foi a cidade de Espinosa/MG. Constatou-se a instituição de mecanismos que viabilizam a participação e controle social da gestão púbica, no entanto esses mecanismos precisam ser apropriados e fortalecidos pela participação ativa da sociedade civil

Contribuições das experiências vivenciadas no PIBID na formação inicial dos licenciandos em matemática

Neste trabalho discutimos as experiências vividas pelos bolsistas do Programa de Iniciação à Docência (PIBID) do Curso de Licenciatura em Matemática da UNESP ao longo do desenvolvimento do projeto numa escola pública estadual da cidade de Ilha Solteira, no Estado de São Paulo e as contribuições dessas experiências para a sua formação inicial. Para isso, apresentamos as ações que vêm sendo desenvolvidas desde o segundo semestre de 2011 e os resultados obtidos. O objetivo central do projeto é incentivar a participação do licenciando em matemática no cotidiano da escola pública, contribuindo para o desenvolvimento de um proceformação que incentive a docência, tomando-se por base a valorização da carreira do magistério. Com base nas ações realizadas na Escola e nas reflexões dos bolsistas, apontamos possíveis contribuições do PIBID para o estabelecimento de um processo de formação que propicie o desenvolvimento de uma postura de professor-pesquisador e que incentive o licenciando no exercício da docência. Para a construção de nossa análise e discussão, consideramos os dados obtidos por meio dos relatórios mensais individuais dos bolsistas, atas das reuniões quinzenais, anotações de campo das atividades e reuniões na escola e relatórios semestrais da professora supervisora da Escola

Alguns aspectos da demonstração em matemática: uma discussão sobre os métodos empregados no desenvolvimento do raciocínio matemático

O presente trabalho tem por objetivo elaborar um referencial teórico que possibilite entender o raciocínio matemático, a natureza da demonstração matemática e os processos envolvidos na construção dessa demonstração. Assim, para elaborar esse referencial, foram utilizadas as pesquisas de Nickerson (2010), que abordam esses três temas que se agrupam e inter-relacionam para possibilitar uma melhor compreensão dos aspectos inerentes aos métodos de demonstração, considerando as seguintes perguntas: onde e quando surgiu a ideia de uma demonstração? O que constitui uma demonstração? O que os matemáticos querem dizer quando usam o termo demonstração? Como as demonstrações são construídas? Como se pode ter certeza de que uma demonstração proposta é válida? Quem é qualificado para julgar a validade de uma demonstração? Além das indagações de Nickerson, optamos por uma orientação histórica, filosófica e matemática para que possamos ter uma reflexão aprofundada sobre os três assuntos ao respondermos essas perguntas. Dando continuidade nesta pesquisa, pretendemos investigar quais as concepções dos alunos de um curso de graduação em Matemática sobre demonstração

Comentário a “A ciência da política de David Hume”

Commented paper reference: FREITAS, V. F. A ciência da política de David Hume. Trans/form/ação: revista de filosofia da Unesp, v. 44, n. 3, p. 401-428, 2021.Referência do artigo comentado: FREITAS, V. F. A ciência da política de David Hume. Trans/form/ação: revista de filosofia da Unesp, v. 44, n. 3, p. 401-428, 2021