3 research outputs found

    Presentation type, perceived credibility, and perceived validity : a document usability analysis

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    This descriptive research investigated usability measures reported by subjects who reviewed procedures formatted as decision tables and numbered lists taken from a microchip product specification document. The research subjects (n = 15) are employees of Agere Systems (headquartered in Allentown Pennsylvania, United States) where this researcher also worked as a technical writer. Subjects represented various national origins and were stratified into two groups of six Eastern and nine Western. The independent variables, presentation type, perceived credibility, and perceived validity were studied for their interaction with the dependent variable, usability. The variable model was queried between the two groups. Three findings included the following: 1. Subjects from Western cultures reported higher scores for perceived credibility and perceived validity when reviewing procedures formatted as tables than those formatted as numbered lists (t = 2.226, p = 0.027). 2. Subjects from Eastern cultures reported higher scores than subjects from Western cultures on measures of perceived credibility when reviewing procedures formatted as both tables and numbered lists (t = 2.822, p = 0.005). 3. Subjects from Eastern cultures reported lower scores than subjects from Western cultures on measures of perceived validity when reviewing procedures formatted as both tables and numbered lists (t = -2.120, p = 0.035). These are preliminary findings; the research was an exploratory effort to derive testable hypotheses for a future study designed to enroll larger populations under more strictly controlled experimental settings

    The influence of graphical format on judgmental forecasting accuracy: lines versus points

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    People made forecasts from real data series. The points in the series were un‐trended and independent. Hence, forecasts should have been on the mean value. However, consistent with previous research on forecasting biases, forecasts were too close to the last data point. It appears that forecasters see positive sequential dependence where none exists. In three experiments, we examined this bias in different types of forecasting task: point forecasting, probability density forecasting, and interval forecasting. In all cases, we found that it was greater when the data series were displayed using continuous line graphs than when it was displayed using discrete point graphs. Consistent with arguments made by Zacks and Tversky (Memory and Cognition, 27:1073, 1999), we suggest that people are more likely to group data together and to see patterns in them when those data are presented in a continuous than in a discrete format. These findings have implications for forecasting practice

    Desenvolvimento de ferramentas de apoio multicritério à decisão em problemas de localização

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    Tese de doutoramento, Estatística e Investigação Operacional (Análise de Sistemas), Universidade de Lisboa, Faculdade de Ciências, 2014Nesta tese, apresenta-se um Sistema de Apoio à Decisão, desenvolvido e implementado com o objectivo de apoiar a tomada de decisão em problemas de localização bicritério que envolvam preocupações ambientais. O apoio é dado em duas fases interactivas distintas, acreditando que os métodos interactivos são a melhor forma de abordar os modelos multicritério. Na primeira fase, recorre-se a um procedimento de optimização combinatória para obter, de forma progressiva e participativa, qualquer solução não dominada dos modelos de localização bicritério implementados. Nesta primeira fase interactiva, destaca-se a importância de ser possível utilizar um Sistema de Informação Geográfica, integrado no Sistema de Apoio à Decisão, para a obtenção de dados relevantes para os modelos em causa, especialmente aqueles que requerem mais preocupações relativamente aos impactos ambientais. O uso do Sistema de Informação Geográfica, ao longo de todo o processo de decisão, também permite uma visualização apelativa e real das soluções interactivamente obtidas. Na segunda fase, caso seja necessário, usa-se a posteriori uma ferramenta de análise multiatributo para estudar em detalhe as soluções de compromisso provenientes da primeira fase. Esta ferramenta corresponde a uma implementação interactiva simples do método conjuntivo, fazendo uso de um gráfico radar como base do procedimento. A ferramenta proposta pretende contornar o problema da compensação, evitando uma agregação intercritério. O método de análise inerente à ferramenta não exige qualquer transformação ou normalização, de forma a assegurar a comparabilidade entre os critérios. De modo a descrever e a validar as potencialidades e as funcionalidades do SABILOC – o Sistema de Apoio à Decisão desenvolvido e implementado, explora-se um caso de estudo de um problema real relativo à localização de estações de transferência de resíduos.In this thesis, we present a two-phase interactive Decision Support System aimed at supporting decision-making concerning bicriteria location models in which the facilities to be located could have environmental impacts. The decision support is provided through two interactive phases, believing that interactive methods are the best way to deal with multicriteria models. First, a combinatorial optimization procedure to obtain, in a progressive and participatory way, any non-dominated solution of the bicriteria location models implemented, is used. In this first phase, we highlight that a Geographic Information System, embedded into the Decision Support System, can be used to obtain relevant data for the models concerned, especially those considering environmental issues. The Geographic Information System also allows, throughout the decision process, visualizing in an appealing and real way the solutions interactively obtained. Next, if necessary, a multiattribute a posteriori analysis tool could also be employed in order to analyze in detail a set of compromise solutions from the first phase. This one stands for a simple interactive implementation of the conjunctive method making use of a radar chart as basis for the procedure. The tool proposed is intended to circumvent the problem of compensation, avoiding aggregation inter-criteria. To use the method inherent to the tool proposed, it is not required any transformation or normalization to insure the comparability between criteria. In order to describe and validate the potentialities and functionalities of SABILOC – the Decision Support System developed and implemented, we present a case study of a real world problem applied to waste transfer station siting.Fundação para a Ciência e a Tecnologia (FCT, Programa de Apoio à Formação Avançada de Docentes do Ensino Superior Politécnico - PROTEC
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