Cumulative dominance and heuristic performance in binary multi-attribute choice

Working paper 895, Department of Economics and Business, Universitat Pompeu FabraSeveral studies have reported high performance of simple decision heuristics in multi-attribute decision making. In this paper, we focus on situations where attributes are binary and analyze the performance of Deterministic-Elimination-By-Aspects (DEBA) and similar decision heuristics. We consider non-increasing weights and two probabilistic models for the attribute values: one where attribute values are independent Bernoulli randomvariables; the other one where they are binary random variables with inter-attribute positive correlations. Using these models, we show that good performance of DEBA is explained by the presence of cumulative as opposed to simple dominance. We therefore introduce the concepts of cumulative dominance compliance and fully cumulative dominance compliance and show that DEBA satisfies those properties. We derive a lower bound with which cumulative dominance compliant heuristics will choose a best alternative and show that, even with many attributes, this is not small. We also derive an upper bound for the expected loss of fully cumulative compliance heuristics and show that this is moderate even when the number of attributes is large. Both bounds are independent of the values of the weights.Postprint (author’s final draft

Ambiguity seeking as a result of the status quo bias

Several factors affect attitudes toward ambiguity. What happens, however, when people are asked to exchange an ambiguous alternative in their possession for an unambiguous one? We present three experiments in which individuals preferred to retain the former. This status quo bias emerged both within- and between-subjects, with and without incentives, with different outcome distributions, and with endowments determined by both the experimenter and the participants themselves. Findings emphasize the need to account for the frames of reference under which evaluations of probabilistic information take place as well as modifications that should be incorporated into descriptive models of decision making.Ambiguity, risk, status quo bias, decision making, uncertainty, Leex

Cumulative dominance and heuristic performance in binary multi-attribute choice

Several studies have reported high performance of simple decision heuristics multi-attribute decision making. In this paper, we focus on situations where attributes are binary and analyze the performance of Deterministic-Elimination-By-Aspects (DEBA) and similar decision heuristics. We consider non-increasing weights and two probabilistic models for the attribute values: one where attribute values are independent Bernoulli randomvariables; the other one where they are binary random variables with inter-attribute positive correlations. Using these models, we show that good performance of DEBA is explained by the presence of cumulative as opposed to simple dominance. We therefore introduce the concepts of cumulative dominance compliance and fully cumulative dominance compliance and show that DEBA satisfies those properties. We derive a lower bound with which cumulative dominance compliant heuristics will choose a best alternative and show that, even with many attributes, this is not small. We also derive an upper bound for the expected loss of fully cumulative compliance heuristics and show that this is moderate even when the number of attributes is large. Both bounds are independent of the values of the weights.Multi-attribute decision making, binary attributes, DEBA, cumulative dominance, performance bounds, Leex

Am I a Bully? A Mixed Methods Phenomenological Study of the Perspectives and Experiences of Girls Who Are Relationally Aggressive

This explanatory mixed-methods, phenomenological study investigated how relationally aggressive females perceive and experience their social world. The first, quantitative phase of the study included 237 students (85 males, 152 females) in grades 6 to grade 8 from four different schools. All students completed the quantitative measures of the study; a peer nomination scale of relational aggression, the Basic Empathy Scale (Joliffe & Farrington, 2006), and a self-concept measure, the Self-Description Questionnaire Short Form (Marsh et al., 2005). Female students whose mean relational aggression score was greater than 1 SD about the class mean, and received votes from more than 30% of the class were identified as relationally aggressive. The second qualitative phase of the study included interviews with 18 females identified as relationally aggressive. To triangulate the data, seven of the students’ teachers were also interviewed. The theoretical framework for this study included resource control theory and symbolic interactionism. The results revealed the complexity of girls’ social environment; in particular the powerful social arena of drama. The results further found the girls’ highly competitive nature that stretched from their social relationships to their extracurricular activities and academics. Most participants had a very positive self-concept and self-esteem, and reported respectful relationships with parents and teachers. However, some teachers raised suspicions around the authenticity of that respect. The findings indicate the need to understand the complex social world of relationally aggressive adolescent girls and the powerful and influential force of drama. Implications of the study’s findings for anti-bullying interventions are discussed

U.S. consumers and electronic banking, 1995-2003

The availability and variety of electronic banking technologies in the marketplace has greatly expanded in recent years. For financial institutions, e-banking technologies can speed processing, reduce costs, and help attract and retain customers. For consumers, they can save time and money and may be more convenient than more traditional ways of banking. This article draws on data from two nationwide surveys to look at consumer use of such products and services as debit cards, pre-authorized debits, and computer banking, particularly as use relates to consumer demographic characteristics and consumer perceptions. ; The data show a consistent increase in the proportion of consumers using a variety of e-banking technologies. Consumer attitudes toward e-banking generally have become more positive over time, with more consumers seeing e-banking as convenient, familiar, easy to use, and secure. The use of some technologies, particularly debit cards, has become more democratized over time, but it is still the case that most e-banking technologies tend to be used by higher income, higher asset, younger, and better educated households. ; E-banking technologies hold the promise of helping families manage their money, pay their bills on time, and avoid overextending themselves with credit. To take full advantage of them, however, consumers need to become aware of the evolving array of e-banking technologies available to them and understand how different technologies fit with their financial management needs. Financial planners and consumer educators, working with both families and financial institutions, can help the promise become a reality.Electronic funds transfers ; Internet banking

Selective attention to conditioned stimuli in human discrimination learning: Untangling the effect of outcome prediction, valence, arousal and uncertainty

What are the neural mechanisms underlying this ability? Are they the same in humans as in other animals? And what are the consequences of damage to this attentional system? These are the questions that this book aims to answer.The preparation of this manuscript was supported by a MRC new investigator award to Lee Hogarth (G0701456)

Kinematics of molecular gas in star-forming galaxies with large-scale ionized outflows

We investigate the kinematics of the molecular gas in a sample of seven edge-on (i > 60°) galaxies identified as hosting large-scale outflows of ionized gas, using ALMA CO(1–0) observations at ∼1 kpc resolution. We build on Hogarth et al., where we find that molecular gas is more centrally concentrated in galaxies which host winds than in control objects. We perform full three-dimensional kinematic modelling with multiple combinations of kinematic components, allowing us to infer whether these objects share any similarities in their molecular gas structure. We use modelling to pinpoint the kinematic centre of each galaxy, in order to interpret their minor- and major-axis position velocity diagrams (PVDs). From the PVDs, we find that the bulk of the molecular gas in our galaxies is dynamically cold, tracing the rotation curves predicted by our symmetric, rotation-dominated models, but with minor flux asymmetries. Most notably, we find evidence of radial gas motion in a subset of our objects, which demonstrate a characteristic ‘twisting’ in their minor-axis PVDs generally associated with gas flow along the plane of a galaxy. In our highest S/N object, we include bi-symmetric radial flow in our kinematic model, and find (via the Bayesian Information Criterion) that the presence of radial gas motion is strongly favoured. This may provide one mechanism by which molecular gas and star formation are centrally concentrated, enabling the launch of massive ionized gas winds. However, in the remainder of our sample, we do not observe evidence that gas is being driven radially, once again emphasizing the variety of physical processes that may be powering the outflows in these objects, as originally noted in H21

Synthesis of ternary sulfide nanomaterials using dithiocarbamate complexes as single source precursors

We report the use of cheap, readily accessible and easy to handle di-isobutyl-dithiocarbamate complexes, [M(S2CNi Bu2)n], as single source precursors (SSPs) to ternary sulfides of iron–nickel, iron–copper and nickel–cobalt. Varying decomposition temperature and precursor concentrations has a significant effect on both the phase and size of the nanomaterials, and in some instances meta-stable phases are accessible. Decomposition of [Fe(S2CNi Bu2)3]/[Ni(S2CNi Bu2)2] at ca. 210–230 �C affords metastable FeNi2S4 (violarite) nanoparticles, while at higher temperatures the thermodynamic product (Fe,Ni)9S8 (pentlandite) results. Addition of tetra-isobutyl-thiuram disulfide to the decomposition mixture can significantly affect the nature of the product at any particular temperature-concentration, being attributed to suppression of the intramolecular Fe(III) to Fe(II) reduction. Attempts to replicate this simple approach to ternary metal sulfides of iron–indium and iron–zinc were unsuccessful, mixtures of binary metal sulfides resulting. Oleylamine is non-innocent in these transformations, and we propose that SSP decomposition occurs via primary–secondary backbone amide-exchange with primary dithiocarbamate complexes, [M(S2CNHoleyl)n], being the active decomposition precursors

Ultra-brief breath counting (mindfulness) training promotes recovery from stress-induced alcohol-seeking in student drinkers

This is the final version. Available on open access from Elsevier via the DOI in this recordThe therapeutic effect of mindfulness interventions on problematic drinking is thought to be driven by increased resilience to the impact of stress on negative mood and alcohol-seeking behaviour, but this claim needs empirical support. To address this hypothesis, the current study tested whether brief training of one component of mindfulness – breath counting – would reduce drinkers’ sensitivity to the effect of noise stress on subjective mood and alcohol-seeking behaviour. Baseline alcohol-seeking was measured by choice to view alcohol versus food thumbnail pictures in 192 student drinkers. Participants then received a 6-minute audio file which either trained breath counting or recited a popular science extract, in separate groups. All participants were then stressed by a loud industrial noise and alcohol-seeking was measured again, simultaneously (to quantify the change from baseline). Subjective mood was measured after all three stages (baseline, post intervention, post stress test). The breath counting group were instructed to deploy this technique during the stress test. Results showed that the breath counting versus control intervention improved subjective mood relative to baseline, attenuated the worsening of subjective mood produced by stress induction, and accelerated recovery from a stress induced increase in alcohol-seeking behaviour. Exploratory moderation analysis showed that this accelerated recovery from stress induced alcohol-seeking by breath counting was weaker in more alcohol dependent participants. Mindfulness therapies may improve problematic drinking by increasing resilience to stress induced negative mood and alcohol-seeking, observed in this study. The weaker therapeutic effect of breath counting in more dependent drinkers may reveal limitations to this intervention strategy.Medical Research Council (MRC)Alcohol Research U