Handling protest responses in contingent valuation surveys

OBJECTIVES: Protest responses, whereby respondents refuse to state the value they place on the health gain, are commonly encountered in contingent valuation (CV) studies, and they tend to be excluded from analyses. Such an approach will be biased if protesters differ from non-protesters on characteristics that predict their responses. The Heckman selection model has been commonly used to adjust for protesters, but its underlying assumptions may be implausible in this context. We present a multiple imputation (MI) approach to appropriately address protest responses in CV studies, and compare it with the Heckman selection model. METHODS: This study exploits data from the multinational EuroVaQ study, which surveyed respondents' willingness-to-pay (WTP) for a Quality Adjusted Life Year (QALY). Here, our simulation study assesses the relative performance of MI and Heckman selection models across different realistic settings grounded in the EuroVaQ study, including scenarios with different proportions of missing data and non-response mechanisms. We then illustrate the methods in the EuroVaQ study for estimating mean WTP for a QALY gain. RESULTS: We find that MI provides lower bias and mean squared error compared with the Heckman approach across all considered scenarios. The simulations suggest that the Heckman approach can lead to considerable underestimation or overestimation of mean WTP due to violations in the normality assumption, even after log-transforming the WTP responses. The case study illustrates that protesters are associated with a lower mean WTP for a QALY gain compared with non-protesters, but that the results differ according to method for handling protesters. CONCLUSIONS: MI is an appropriate method for addressing protest responses in CV studies

A diversidade das resoluções de requalificação de espaço público num bairro popular e central de Lyon: o caso das praças Djebraïl Bahadourian e Gabriel Péri

Au début des années 2000, la Communauté Urbaine de Lyon a réaménagés deux places, distant de cent mètres entre elles : la place Bahadourian, livrée en 2002, et la place Gabriel Péri en 2004. Malgré leur contemporanéité et leur proximité géographique, les deux aménagements diffèrent dans leur rapport aux usages présents avant l’intervention. Le premier propose d’accueillir la diversité des pratiques existantes, en prévoyant plusieurs équipements, tandis que le deuxième est marqué par une volonté de supprimer toute prise pour des séjours statiques et prolongés, en recherchant la fluidité des déplacements. Cet article retrace les processus de production de ces deux espaces publics, en montrant comment les problèmes et résolutions d’aménagement ont été construits, en explorant la marge de manœuvre laissée par des contraintes de niveaux supérieur, le rôle des jeux d’acteurs et les discours et outils justifiant ces différences de traitement des deux espaces.No princípio dos anos 2000, a Comunidade Urbana de Lyon requalificou duas praças a cem metros uma da outra: a praça Bahadourian, terminada em 2002, e a praça Gabriel Péri em 2004. Apesar de serem contemporâneas e geograficamente próximas, as duas operações diferem na sua postura perante os usos instalados antes da intervenção. A primeira propõe-se a integrar a diversidade de práticas existente, prevendo vários equipamentos, enquanto a segunda se caracteriza por uma tentativa de suprimir todos os incentivos a uma estadia prolongada, procurando a fluidez das deslocações. Este artigo restitui os processos de produção dos dois espaços, mostrando como os problemas e as soluções para a requalificação foram construídos. Aborda ainda a margem de manobra permitida por constrangimentos de nível superior, o papel dos actores e os discursos e instrumentos que justificam essas diferenças de tratamento dos dois espaços

Taking "use" into account in the production of public space in Lyon, Louvain-la-Neuve and Lisbon: contexts, methods and results

Issues of public space use have become a paramount subject of research in the recent past. While research of an overtly operative outlook has convincingly put forward design and management recommendations for improving the use of public spaces, it has struggled in approaching the issue as the scope of urban policy and planning. This research project aims at contributing to re-placing the problem at an urban scope. It will do so by comparing three very different policy and planning processes which, at an urban scale, explicitly put forward use as a main objective of public space production, namely Lyon, Louvain-la-Neuve and Lisbon. This research adopts an inductive approach to the subject, framed by readings in the intersection of pragmatic sociology, policy and economics/management studies which suggest the explanation of policy outcomes by in-depth analyses of the processes leading to them. However, it maintains a geographical standpoint as it is concerned, as well, with the “spatialization of public policies”, i.e. the spaces that are actually produced by said processes and the dynamics of use taking place therein

Factors of good public space use

This paper presents a literature review of some of the most relevant work in the field of urban planning on the relationship between the characteristics of public spaces and their use. The synthesis put forward focuses on the characteristics of public spaces which contribute to their intense use. The former relate to urban form and public space design and management

Infoxicación : exceso y mengua en la sociedad de información

O conceito de intoxicação informativa é um conceito com longas raízes na cultura europeia, prenhe de críticas que se começam a desenhar desde os princípios do século XX. Procuraremos dar nesta alocução conta das contradições que foram levantadas ao longo do século passado e nos princípios deste. Assim, será nosso objectivo tematizar os efeitos da circulação de informação ao nível individual, procurando determinar como o conceito de ‘autenticidade’ e ‘vida autêntica’ se vão mostrando moduladores na hora de analisar a pessoa humana na sua singularidade. Convocaremos autores como M. Heidegger, O. Spengler, L. Mumford, W. Benjamin e Günther Anders. Passaremos depois à arqueologia que começa a desenhar-se em França no período dos pós-guerra, com autores como Michel Foucault, Jean-François Lyotard e Jacques Derrida. Será depois a partir dos pensadores contemporâneos que traçaremos essas contradições que se dão desenhando entre ser-se ‘pessoa’ e ser-se ‘receptor passivo’ em autores como Jean Baudrillard, Paul Virilio, Vilém Flusser e recentemente com Jean-Luc Nancy. Por oposição ao elemento pessoal, traçaremos os efeitos possíveis que o excesso de informação tem a nível social ou da comunidade, procurando desmontar o conceito de ‘criação do mundo’ a partir de pensadores actuais, nomeadamente a partir de Peter Sloterdijk e dos princípios traçados por Daniel L. Schacter em relação à memória social e colectiva

Between tradition and innovation: the teaching of English in Portugal at the turn of the century

Apart from a few individual initiatives that have focused on particular aspects of the teaching of English in Portugal, the history of this teaching is still to be written. And at a time when there is generalized uncertainty about a dominant approach of foreign language teaching in general it would be very helpful if a structured overview of what has been done in the past - covering not only its successes but also its failures - would certainly help present-day teachers of English in Portugal..

Melhoria de eficiência industrial numa unidade de processamento de borracha

For companies to remain competitive in these days’ market environment, they must respond to client needs in terms of service level, demand variety and product quality. As such, methodologies like lean philosophy are used with the intent of improving operational processes, increasing the use of resources and reducing waste. This work was developed in a production unit belonging to Procalçado, S.A., a company in the footwear industry. The company wanted to find solutions for the high complexity of operations and production delays in its raw material processing unit, which had two rubber sole production units as its internal clients. The project’s goals were based on improving production flows in the rubber processing unit, thus reducing WIP and production lead times. With this in mind, the existing operational processes in the unit were analysed and documented. The initial problem’s causes were identified. Finally, improvement measures for the unit were proposed and implemented. Lean tools and production sequencing methods supported these implementations. Those solutions resulted in a decrease in product reprocessing, thanks to the creation of a preventive maintenance culture, a visual management system and an overall improvement in organization of space and workstations. Furthermore, WIP levels were reduced substantially, with an improved production control and improved product flow.Atualmente, para as empresas se manterem competitivas no mercado, necessitam de responder às necessidades do cliente em termos de nível de serviço, variedade da procura e qualidade do produto. Para isso, metodologias como a filosofia lean são aplicadas de maneira a melhorar processos, a aumentar a utilização dos recursos e a reduzir desperdícios. Este trabalho foi desenvolvido numa unidade da Procalçado, S.A., empresa pertencente à indústria do calçado. A empresa pretendia encontrar soluções para a elevada complexidade de operações e atrasos de produção na sua unidade de processamento de matéria-prima, que tinha como clientes internos duas unidades de produção de solas de borracha. O projeto teve como objetivo melhorar o fluxo de produção na unidade de processamento de borracha, por forma a reduzir o WIP e os lead times de produção. Neste sentido, os processos operacionais no setor foram analisados e documentados. As causas do problema em questão foram identificadas, sendo que, finalmente, foram propostas e implementadas medidas de melhoria para a unidade. As melhorias apoiam-se em ferramentas lean, bem como em métodos de sequenciamento de produção. Essas ações de melhoria resultaram numa redução da taxa de reprocessamento de materiais devido à implementação de uma cultura de manutenção preventiva em equipamentos, à criação de sistemas de gestão visual e à organização do espaço e dos postos de trabalho. Além disso, os níveis de WIP reduziram substancialmente, com o auxílio de um maior controlo de produção resultando na libertação de espaço na unidade.Mestrado em Engenharia e Gestão Industria

Growing Artificial Societies to Support Demand Modelling in Mobility-as-a-Service Solutions

Tráfego intenso, congestionamentos e tempos de deslocamento mais longos são consequência doaumento da população, da continuação da posse de carro próprio e do fim do transporte público derota fixa. Embora esta situação tenha criado alguma pressão sobre as autoridades governamentaispara lidar com as questões acima mencionadas, isso também pode provar ser uma oportunidadepara numa nova abordagem ao conceito de mobilidade.Uma possível solução passaria pela Mobilidade como serviço (MaaS), um conceito relativa-mente novo no paradigma de mobilidade, que promete mudar em termos do que é mobilidade ecomo ela é entregue aos usuários finais. Fazendo uso das atuais infraestruturas físicas e meios detransporte, e combinando-as com tecnologias da informação e comunicação (TICs), o MaaS temcomo principal objetivo entregar a mobilidade aos usuários finais como um serviço que é consum-ido através de uma plataforma. Essas plataformas são baseadas em modelos de mercado, onde umregulador é responsável pelo equilíbrio entre oferta e demanda.As Sociedades Artificiais (AS) pretendem ser uma forma de simular sociedades reais, atravésde um modelo artificial de agentes proativos e dinâmicos, capazes de interagir entre eles. Essesagentes são capazes de se comunicar entre eles através de uma rede social, onde várias regras sãousadas para disciplinar e normalizar os agentes e o ambiente onde eles estão contidos.A modelação da demanda (DM) é um conceito que permite prever com precisão a demandapor algum mercado, dependendo do equilíbrio entre oferta e demanda. Além disso, tendo em contaa presença do regulador, responsável pela manutenção e implementação de políticas de regulação,o DM facilita a modelação de toda essa dinâmica.A análise dos melhores modelos de serviços, pode ser muito benéfica para o MaaS, uma vezque a modelação de metodologias novas e mais precisas poderia melhorar os processos de decisãopresentes nos vários modelos de mercado do MaaS.Este trabalho tem como objetivo desenvolver um metamodelo cognitivo de sistema multi-agente capaz de descrever a dinâmica do conceito de MaaS. O metamodelo desenvolvido deveser capaz de suportar diferentes estratégias deliberativas e de tomada de decisão em ambientes demercado de serviços abertos, com aplicações de mobilidade em Cidades Inteligentes. O objetivo édesenvolver uma plataforma de apoio à decisão para apoiar a análise e implementação de políticasde incentivo que promovam o desenvolvimento do conceito de MaaS. Esta plataforma fará uso detécnicas de modelagem e simulação de sistemas complexos recorrendo às metáforas de sociedadesartificiais e sistemas multiagentes.Huge traffic, congestion, longer commute times, are a consequence of the increase in population,continuation of universal car ownership and demise of fixed route public transport. While thissituation have been creating some pressure on the governmental authorities to tackle the afore-mentioned issues, this could also prove to be an opportunity to try a different approach regardingthe concept of mobility.One particular solution could be Mobility-as-a-Service (MaaS), a relatively new concept in amobility paradigm that promises a big shift in terms of what is mobility and how it is deliveredto the end-users. Making use the current physical infrastructures and transport means, and com-bining them with information and communications technologies (ICTs), MaaS has the main goalto delivery the mobility to the end-users as a service that is consumed through a platform. Theseplatforms are based on market models, where there a regulator that is responsible for the balancethe balance between supply and demand.Artificial Societies (AS) aims to be a way to simulate real societies, through an artificial modelof proactive and dynamic agents, able to interact between them. These agents are able to commu-nicate between them through a social network, where several rules are used to discipline and normboth agents and the environment where they are contained.Demand modelling (DM) is a concept that allows accurately to forecast the demand regardingsome market, depending of the balance between supply and demand. Moreover, taken into accountthe presence of the regulator, which is responsible for the maintenance and implementation ofpolicies, DM facilitates the modelling of all this dynamic.The analysis of the best service models, could prove greatly beneficial for MaaS, as modelingnew and more accurate methodologies could better the decision processes present in the variousmarket models of MaaS.This work aims to develop a cognitive multi-agent system meta-model able to describe thedynamic of MaaS concept. The developed meta-model should be able to support different de-liberative and decision making strategies in open service market environments, with mobility ap-plications in Smart Cities. The purpose is to develop a decision support platform to support theanalysis and implementation of incentive policies that promote the development of the concept ofMaaS. This platform will make use of techniques of modeling and simulation of complex systemsresorting to the metaphors of artificial societies and multi-agent systems

Modular Logic Programming: Full Compositionality and Conflict Handling for Practical Reasoning

With the recent development of a new ubiquitous nature of data and the profusity of available knowledge, there is nowadays the need to reason from multiple sources of often incomplete and uncertain knowledge. Our goal was to provide a way to combine declarative knowledge bases – represented as logic programming modules under the answer set semantics – as well as the individual results one already inferred from them, without having to recalculate the results for their composition and without having to explicitly know the original logic programming encodings that produced such results. This posed us many challenges such as how to deal with fundamental problems of modular frameworks for logic programming, namely how to define a general compositional semantics that allows us to compose unrestricted modules. Building upon existing logic programming approaches, we devised a framework capable of composing generic logic programming modules while preserving the crucial property of compositionality, which informally means that the combination of models of individual modules are the models of the union of modules. We are also still able to reason in the presence of knowledge containing incoherencies, which is informally characterised by a logic program that does not have an answer set due to cyclic dependencies of an atom from its default negation. In this thesis we also discuss how the same approach can be extended to deal with probabilistic knowledge in a modular and compositional way. We depart from the Modular Logic Programming approach in Oikarinen & Janhunen (2008); Janhunen et al. (2009) which achieved a restricted form of compositionality of answer set programming modules. We aim at generalising this framework of modular logic programming and start by lifting restrictive conditions that were originally imposed, and use alternative ways of combining these (so called by us) Generalised Modular Logic Programs. We then deal with conflicts arising in generalised modular logic programming and provide modular justifications and debugging for the generalised modular logic programming setting, where justification models answer the question: Why is a given interpretation indeed an Answer Set? and Debugging models answer the question: Why is a given interpretation not an Answer Set? In summary, our research deals with the problematic of formally devising a generic modular logic programming framework, providing: operators for combining arbitrary modular logic programs together with a compositional semantics; We characterise conflicts that occur when composing access control policies, which are generalisable to our context of generalised modular logic programming, and ways of dealing with them syntactically: provided a unification for justification and debugging of logic programs; and semantically: provide a new semantics capable of dealing with incoherences. We also provide an extension of modular logic programming to a probabilistic setting. These goals are already covered with published work. A prototypical tool implementing the unification of justifications and debugging is available for download from http://cptkirk.sourceforge.net