Marco Aurélio Stumpf González

Mass Appraisal With Genetic Fuzzy Rule-Based Systems

The use of mass appraisal techniques is a common practice in real estate taxation. The models of real estate market have several sources of imprecision, such as errors in the transitions between submarkets, generating difficulties to construct mass appraisal models. Fuzzy Rule-Based Systems (FRBS) are able to generate flexible systems and may be useful in considering vagueness or imprecision presents in real estate market. This paper verifies the extraction of fuzzy rules from real estate data through genetic algorithms, performing Genetic Fuzzy Rule-Based Systems (GFRBS). These GFRBS used TSK rules, which are formed by linear equations and may be seen as hedonic models. Two approaches were tested. The first one is a GFRBS based on the gross building area of the properties, tested in systems with 3 to 7 rules. In another view, a system of rules based on location of the properties was constructed, in which each rule is specialized in determined region, and contributes to a general estimate. The systems were implemented with data of the city of Porto Alegre (Brazil), comparing the fuzzy models with a traditional hedonic regression model. The results have indicated the potential of fuzzy rules in mass appraisal.

A new approach to spatial analysis in CAMA

Purpose – Available literature claims that location is a key attribute in the housing market. However, the impact of this attribute is difficult to measure and the traditional hedonic approach using subjective assessments is problematic. This paper seeks to explore trend surface analysis technique, attempting to provide an alternative way to measure location values.Design/methodology/approach – TSA works in a similar way to other response surface methods but it is implemented directly in regression models, using a set of combinations of the co‐ordinates of properties in several power degrees. It can also be implemented in artificial neural networks, taking advantage of the neural ability in non‐linear domains. This work presents a comparison between traditional regression approach, error modelling, response surfaces, and TSA. ANN is also used to estimate some models, comparing their results. The objective is to verify the behaviour of TSA in hedonic models. A case study was carried using data of over 30,0...

A certificação de desempenho ambiental de prédios: exigências usuais e novas atividades na gestão da construção

Sistemas de certificacao ambiental de edificios tem sido desenvolvidos, em diversos paises, em decorrencia dos significativos impactos ambientais causados pela construcao civil. No Brasil ja existem alguns empreendimentos certificados e outros em processo de certificacao, ainda que seguindo sistemas estrangeiros. Em sintese, esses sistemas de certificacao sao compostos de criterios de avaliacao que consideram diferentes aspectos ambientais, organizados em categorias. A certificacao e concedida de acordo com o desempenho do edificio diante desses criterios. O presente artigo discute as peculiaridades na gestao da construcao de edificios candidatos a essa modalidade de certificacao, identificando-se atividades usuais e novas atividades, quando comparadas a gestao da construcao de edificios, sem o interesse na certificacao. Como estrategia de pesquisa realizou-se um estudo de caso durante a fase de producao de um predio comercial que buscou a certificacao de nivel Gold do sistema norte-americano LEED. Os resultados apontam que o sistema de certificacao exigiu atividades usualmente realizadas na fase de projeto, porem com um nivel maior de envolvimento por parte dos projetistas. Na fase de producao, alem de maiores exigencias nas atividades tradicionalmente realizadas, identificaram-se novas atividades de gestao para a empresa construtora, assim como a necessidade de disponibilizar informacoes tecnicas dos produtos por parte dos fornecedores de materiais e componentes.

Automated Valuation Methods in Real Estate Market—a Two-Level Fuzzy System

This chapter presents a scheme to Automated Valuation Modelling that joined a two level-fuzzy system with multiple regression hedonic price models in Automated Valuation Modelling. This scheme is based in two main characteristics of real estate market: location and segmentation in sub-markets. Location is recognized as a very important element of real estate market and price of each unity is severely affected by its urban position. By another side, market is divided in several segments (based on diversity of real properties), although there is not a clear division point. Actually, there is a trespass among market segments, which is not abrupt, but continuous. Fuzzy logic permits to take in account continuity of variables. Then, fuzzy logic may contribute to improve Automated Valuation Modelling systems.

Ampliaciones en viviendas sociales: Estudio de caso en Ivoti -Brasil

Social housing built in Brazil is often modified by users, usually soon after construction is finished, for both functional and economic reasons. Apparently, standard designs that public housing programs offer do not meet the needs of users. From this evidence, this study aims to examine a real situation and analyze changes made to social housing in the city of Ivoti, on southern Brazil. The case study examined 32 residences located in three districts of the city. It was found that 97% of the examined properties were expanded after the units were delivered. As a result, it can be concluded that the projects provided by the government agencies are not in accordance with the requirements of users in this region. Rev. ing. constr. [online]. 2013, vol.28, n.3, pp. 237-250. ISSN 0718-5073. http://dx.doi.org/10.4067/S0718-50732013000300002

Identificación de los requisitos del usuario en el sector de la construcción bajo mecanismos de descubrimiento del conocimiento

The purpose of this paper is to investigate how the knowledge of real estate market can be used to support user requirement identification. A construction project well adjusted to the user requirements increase value and causes minors changes during its life cycle. As a consequence, renewal, refurbishments, and demolition are less present, reducing waste generation, reworking and material consumption. It is especially important in housing customization markets. However, one of the challenges faced by designers is frequently concerned about how properly to identify user requirements, wishes and needs, which are on the essence of the briefing phase. In this context, real estate data can be useful to designers, since it reflects the users’ evaluation of the building attributes. The research strategy uses a knowledge discovery mechanism, composed by five steps: (1) formulation of a general database; (2) specific data selection using Case-Based Reasoning; (3) enrichment of data-sample; (4) development of hedonic price models using regression analysis; and (5) simulation of the value of design alternatives. Based on an application of an hedonic price model, using data from the medium-class housing market of Porto Alegre, Brazil, the main results indicate that adjusted price models have sufficient detailing and statistical precision to support decisions in the initial stage of design.

Un estudio sobre el mejoramiento del inventario de edificios sociales con énfasis en la rehabilitación de fachadas

Some part of the stock of social housing in Brazil has deteriorted due to lack of maintenance. The depreciation of these constructions, especially in the case of housing projects, reduces the quality of environment, with social and economic consequences for inhabitants, and also for the region. Building renewal is an important action to recover the lost quality of the life. The increase in life time of housing may also reduce the construction and demolition waste production. One of the most important aspects is the facade, which influences the value of the property and the perception of the society about the inhabitants. This work presents a study of improving and facade renewal of social housing in Sao Leopoldo, a southern Brazilian city.