Artigos Acadêmicos e Noticiosos
URI permanente desta comunidadehttps://repositorio.insper.edu.br/handle/11224/3226
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Artigo Científico Subway expansion, job accessibility improvements, and home value appreciation in four global cities: Considering both local and network effects(2022) Adriano Borges Costa; ADRIANO BORGES FERREIRA DA COSTA; Ramos, Camila; Zheng, SiqiWe explore the potential of incorporating accessibility analysis in addressing the impact of subway expansions on the real estate market. We first demonstrate that by using increases in accessibility to jobs as a continuous treatment variable, rather than adopting a binary station dummy approach, we achieve better goodness-of-fit in a quasiexperimental econometric analysis. Furthermore, accessibility measures allow the exploration of impacts beyond the local effects around new subway stations, shedding light on a network impact that has been largely overlooked to date. To increase the external validity of our findings, we apply the same analysis to the cities of Santiago (Chile), Sao Paulo (Brazil), Singapore, and Barcelona (Spain). and then explore the emergent patterns. We argue that the integration of urban economics and transportation analysis via the use of accessibility measures constitutes an innovation in the empirical approach commonly adopted in the literature. The use of such measures in causal empirical studies on transportation impacts can yield more robust and comprehensive results and capture nuanced spatial heterogeneity effects.Artigo Científico Exploring the causal effects of the built environment on travel behavior: a unique randomized experiment in Shanghai(2022) Chen, Faan; ADRIANO BORGES FERREIRA DA COSTAExperimental designs have been recognized as the gold standard for establishing causal mechanisms. However, the application of such designs is complicated by factors such as excessive costs, time consumption, ethical concerns, and political impossibility. Nevertheless, the Chinese government’s replacement housing efforts provide a unique randomized experiment for exploring the causal effects of the built environment on travel behavior. Accordingly, based on a large-scale survey on travel patterns under an experimental design in Shanghai, this study employs a two-step modeling approach, involving logit and Tobit models, to identify the built environment’s effects on auto ownership and vehicle kilometers traveled (VKT). We found that transit service improvements play a stronger role in reducing auto-drive than compact and diverse land-use characteristics. Increasing residential and employment density, as well as land-use mix, discourages car ownership, which in turn reduces VKT, but with lower elasticities than transportation system variables. The findings provide additional evidence and referential estimate for how land-use and transport strategies and policies designed to create a compact, mixed-use, and highly accessible built environment can be used in reducing auto driving. This study expands the VKT reduction elasticities’ database regarding the built environment across global spatial contexts, serving as a model for similar studies elsewhere in the world.Artigo Científico A privacidade e o mercado de dados pessoais(2016) Silveira, Sergio Amadeu; RODOLFO DA SILVA AVELINO; Souza, JoyceO artigo apresenta a estrutura e a dinâmica do mercado de dados pessoais. Mostra a dimensão econômica do dado pessoal para a economia da informação. Apresenta as quatro camadas do mercado de dados: a coleta e armazenamento de informações; o processamento e a mineração de dados; a análise e a formação de amostras; e a modulação. Essas camadas se articulam e se misturam dependendo da organização das empresas que integram esse mercado. O artigo mostra ainda os elementos do mercado de dados no Brasil a partir de entrevistas realizadas com seus operadores. Por fim, indica a relevância do direito à privacidade para impor limites às atividades da economia da interceptação de dados.Artigo Científico Beyond the Agreement: Dilemmas in Contracting for the Transfer of Management Practices(2022) SANDRO CABRAL; SERGIO GIOVANETTI LAZZARINI; Domingos, Fernando Deodato; RICARDO PAES DE BARROSArtigo Científico Identification of segregated regions in the functional brain connectome of autistic patients by a combination of fuzzy spectral clustering and entropy analysis(2016) Sato, João Ricardo; Balardin, Joana; MACIEL CALEBE VIDAL; André FujitaBackground: Several neuroimaging studies support the model of abnormal development of brain connectivity in patients with autism-spectrum disorders (ASD). In this study, we aimed to test the hypothesis of reduced functional network segregation in autistic patients compared with controls. Methods: Functional MRI data from children acquired under a resting-state protocol (Autism Brain Imaging Data Exchange [ABIDE]) were submitted to both fuzzy spectral clustering (FSC) with entropy analysis and graph modularity analysis. Results: We included data from 814 children in our analysis. We identified 5 regions of interest comprising the motor, temporal and occipito-temporal cortices with increased entropy (p < 0.05) in the clustering structure (i.e., more segregation in the controls). Moreover, we noticed a statistically reduced modularity (p < 0.001) in the autistic patients compared with the controls. Significantly reduced eigenvector centrality values (p < 0.05) in the patients were observed in the same regions that were identified in the FSC analysis. Limitations: There is considerable heterogeneity in the fMRI acquisition protocols among the sites that contributed to the ABIDE data set (e.g., scanner type, pulse sequence, duration of scan and resting-state protocol). Moreover, the sites differed in many variables related to sample characterization (e.g., age, IQ and ASD diagnostic criteria). Therefore, we cannot rule out the possibility that additional differences in functional network organization would be found in a more homogeneous data sample of individuals with ASD. Conclusion: Our results suggest that the organization of the whole-brain functional network in patients with ASD is different from that observed in controls, which implies a reduced modularity of the brain functional networks involved in sensorimotor, social, affective and cognitive processing.Artigo Científico A Statistical Method to Distinguish Functional Brain Networks(2017) Fujita, André; MACIEL CALEBE VIDAL; Takahashi, Daniel Y.One major problem in neuroscience is the comparison of functional brain networks of different populations, e.g., distinguishing the networks of controls and patients. Traditional algorithms are based on search for isomorphism between networks, assuming that they are deterministic. However, biological networks present randomness that cannot be well modeled by those algorithms. For instance, functional brain networks of distinct subjects of the same population can be different due to individual characteristics. Moreover, networks of subjects from different populations can be generated through the same stochastic process. Thus, a better hypothesis is that networks are generated by random processes. In this case, subjects from the same group are samples from the same random process, whereas subjects from different groups are generated by distinct processes. Using this idea, we developed a statistical test called ANOGVA to test whether two or more populations of graphs are generated by the same random graph model. Our simulations' results demonstrate that we can precisely control the rate of false positives and that the test is powerful to discriminate random graphs generated by different models and parameters. The method also showed to be robust for unbalanced data. As an example, we applied ANOGVA to an fMRI dataset composed of controls and patients diagnosed with autism or Asperger. ANOGVA identified the cerebellar functional sub-network as statistically different between controls and autism (p < 0.001).Artigo Científico Economic Freedom and the Determinants of the Bank Spread in South America(2022) Maciel, Vladimir Fernandes; Gamboa, Ulisses Ruiz de; Alves, Rafael Estevão GarciaThis paper performs panel data analysis to test the existence of an inverse relationship between bank spreads and the degree of economic freedom in South American countries between 2000 and 2020. In the late 1990s, South America began a process of financial sector reforms, which included in almost all countries the liberalization of interest rates (instead of capping) and the elimination of direct credit allocation mechanisms. By hypothesis, it is expected that the greater the economic freedom, the lower the degree of financial regulation. This would reduce the transaction costs of financial institutions and contribute to reducing the banking spread (assuming constant credit risk). The traditional methodology is applied here, complemented by unit root and cointegration tests, in addition to impulse-response function analysis, in the context of panel autoregressive vectors (VAR). The results show that economic freedom and monetary credibility (component area of the EFW, Economic Freedom of the World index) negatively affect the value of the spread, with long-run effects as well.Artigo Científico Performance Measurement in a Brazilian Clinical Trials Unit(2021) Aquino, Thomaz Martins de; Bonizio, Roni Cleber; Padua, Silvia Ines Dallavalle de; Coelho, Eduardo Barbosa; Faustino, Gabriela GimenezBackground: There is growing interest on costs of clinical trials; critical topic for business decision making; therefore, the aim of this work is to identify how a successful Brazilian case measures its economic performance even with restriction regarding its accounting data. Methods: Single case qualitative method. Interviews with four people of different hierarchical levels and the analysis of the 2005 balance sheet, payrolls and payment slips were carried out. Results: Besides indicating how the clinical research unit of the case measures its results, a diagram of how other units and organizations could follow such procedure to carry out their own performance measurement was pointed out as well. Conclusion: The use of contribution margin and break-even point for the performance calculation benefited the managerial decision-making of the unit studied, serving as basis for its own strategy and use of its idleness. This is a reference model for decision-making of managers in other research units.Artigo Científico Agency Conflicts Between Controlling and Minority Shareholders in the Distribution of Dividends in Brazilian Companies(2022) Kuronuma, Cleiton Ricardo; Okimura, Rodrigo Takashi; Sale, George Andre WillrichObjective: This paper aims to investigate whether the dividend policy is influenced by the shareholding concentration of publicly traded companies in Brazil. Methodology: This research was elaborated through panel regression analysis empirical tests, considering the period from 2013 to 2016. Originality/ Relevance: In Brazil, shareholding is usually concentrated in a small number of shareholders. In this scenario, controlling shareholders often end up having a great influence on management. As a result, agency conflicts may arise (Dalmácio & Corrar, 2007), mainly because controlling shareholders, who have the right to vote, are not always the holders of the preferred shares, which also share dividends (Lopes & Walker, 2008). Thus, according to the Agency Theory, the possibility could be raised of the principal - the controlling shareholder aiming to maximize its individual utility (Martinez, 2001). Main Results: It was verified that there is a positive relationship between the shareholding concentration and the distribution of dividends, that is, the higher the shareholding concentration, the greater the dividend distribution. Contributions: For this research, it were used statistical tests utilizing the panel data regression technique and estimators of Weighted Least Square (WLS), in which were observed the results of the regressions of the total sample (1.440 observations) and four industry sectors, which showed evidence that, there is at least one variable with a statistically significant power (non-cyclical consumption, financial, health, and information technology).Artigo Científico Análise e aplicação dos pronunciamentos US GAAP SFAS 109, SFAS 141, ASC 740 e ASC 805: um estudo de caso no Brasil(2022) Toaldo, Alexsandro; Mendonça Neto, Octavio Ribeiro de; Oyadomari, José Carlos Tiomatsu; Peters, Marcos Reinaldo SeverinoEste estudo investiga como os pronunciamentos do US-GAAP relacionados a combinações de negócios e imposto de renda diferido mudaram substancialmente ao longo do tempo. O estudo de caso foi realizado a partir de dados coletados por meio da observação direta da equipe de controladoria local envolvida no processo de combinação de negócios. Os resultados nos casos de (a) combinação de negócios e (b) imposto de renda diferido, conclui-se, respectivamente: (a) para US-GAAP é utilizado o método de aquisição contábil e (b) demonstra que tanto SFAS 109 quanto ASC 740, continua a orientar, de forma genérica e inadequada, o procedimento de reconhecimento contábil relativo ao imposto de renda diferido em caso específico de combinação de negócios. A pesquisa contribui tanto para a prática quanto para a acadêmica. Apesar de amplamente utilizados, as combinações de negócios e o imposto de renda diferido não são objeto de pesquisas profundas e continuadas. Finalmente, este trabalho não analisa o efeito das combinações de negócios e impostos diferidos para fins de IFRS.