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Bells Corners, Canada

Agent-based models are more likely to generate accurate outputs if they incorporate valid representations of human agents than if they don't. The present article outlines three research methodologies commonly used for explicating the cognitive processes and motivational orientations of human judgment and decision making: policy capturing, information seeking, and social choice. Examples are given to demonstrate how each methodology might be employed to supplement more traditional qualitative methods such as interviews and content analyses. Suggestions for encoding results of the three methodologies in agent-based models are also given, as are caveats about methodological practicalities. © 2015 JASSS. Source

Hill P.L.,University of Illinois at Urbana - Champaign | Hill P.L.,Carleton University | Payne B.R.,University of Illinois at Urbana - Champaign | Jackson J.J.,Washington University in St. Louis | And 2 more authors.
Journals of Gerontology - Series B Psychological Sciences and Social Sciences

Objectives. This study examined whether perceived social support predicted adaptive personality change in older adulthood, focusing on the trait of conscientiousness. We tested this hypothesis both at the broad domain level and with respect to the specific lower order facets that comprise conscientiousness: order, self-control, industriousness, responsibility, and traditionalism. Methods. A sample of 143 older adults (aged 60-91) completed measures of conscientiousness and social support during 2 assessments 7 months apart. Results. Social support and conscientiousness were positively correlated among older adults. Moreover, older adults who perceived greater social support at baseline were more likely to gain in conscientiousness over time. The magnitude of this effect was relatively similar across the order, self-control, and industriousness facets. Discussion. Perceived social support provides multiple benefits later in life, and the current results add to this literature by showing that it also promotes conscientiousness. As conscientiousness is linked to a variety of positive outcomes later in life, including health, future research should examine whether conscientiousness change may be an important mechanism through which social support enhances resilience in older adulthood. © 2013 The Author. Source

Gauthier R.C.,125 Colonel By Drive
Optics Communications

The presence of structural disorder in a photonic crystal is examined through the rotational symmetry extracted from a Fourier-Bessel approach to solving Maxwell's wave equation in cylindrical space. A dielectric correlation function is proposed that relates the original structure to the disordered structure and when normalized it can be used to quantify the level of any disorder mechanism present. It is shown that the presence of disorder causes a mixing of localized and extended states and that the mixing can be directly attributed to "off diagonal" elements of the eigen-matrix and rotational symmetry breaking within the structure. The properties of disorder in an ordered structure are used to identify locations of local order in disordered structures. The Fourier-Bessel analysis of a disordered structure confirms the presence of localized light states at these sites. © 2015 Elsevier B.V. All rights reserved. Source

Thorngate W.,125 Colonel By Drive | Edmonds B.,Manchester Metropolitan University

Most traditional strategies of assessing the fit between a simulation's set of predictions (outputs) and a set of relevant observations rely either on visual inspection or squared distances among averages. Here we introduce an alternative goodness-of-fit strategy, Ordinal Pattern Analysis (OPA) that will (we argue) be more appropriate for judging the goodness-of-fit of simulations in many situations. OPA is based on matches and mismatches among the ordinal properties of predictions and observations. It does not require predictions or observations to meet the requirements of interval or ratio measurement scales. In addition, OPA provides a means to assess prediction-observation fits case-by-case prior to aggregation, and to map domains of validity of competing simulations. We provide examples to illustrate how OPA can be employed to assess the ordinal fit and domains of validity of simulations of share prices, crime rates, and happiness ratings. We also provide a computer programme for assisting in the calculation of OPA indices. © JASSS. Source

Basu O.D.,125 Colonel By Drive | De Souza N.P.,125 Colonel By Drive
Journal of Water Supply: Research and Technology - AQUA

The impact of water quality parameters such as organic and inorganic matter as well as chlorine species (free chlorine and monochloramine) on the rate of dechlorination by sodium bisulfite (SBS), sodium thiosulfate (STS) and ascorbic acid (AA) were studied. Reaction rate constants determined for the various dechlorination reactions showed that SBS and AA achieved dechlorination at a faster rate than STS. Organic matter present in the test solution increased the rate of dechlorination by STS but not SBS and AA. AA was found to be ineffective for the removal of monochloramine. The effect of dechlorination chemicals on water quality with respect to pH, turbidity and total organic carbon (TOC) was investigated along with the acute toxicity of the chemicals on the aquatic indicator species Daphnia magna. SBS was determined to have an LC50 of 68 mg/L with no toxicity impacts observed when the concentration was ≤ 20 mg/L for D. magna. AA increased the TOC levels in the treated water and resulted in some D. magna mortality at higher levels. STS had the least impact on daphnia mortality rates, but the use of STS for dechlorination resulted in the largest pH change of test waters compared to the other dechlorination chemicals. © IWA Publishing 2011. Source

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