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Causal Models (causal + models)
Selected AbstractsCausality and Causal Models: A Conceptual Perspective,INTERNATIONAL STATISTICAL REVIEW, Issue 3 2006Benito V. Frosini Summary This paper aims at displaying a synthetic view of the historical development and the current research concerning causal relationships, starting from the Aristotelian doctrine of causes, following with the main philosophical streams until the middle of the twentieth century, and commenting on the present intensive research work in the statistical domain. The philosophical survey dwells upon various concepts of cause, and some attempts towards picking out spurious causes. Concerning statistical modelling, factorial models and directed acyclic graphs are examined and compared. Special attention is devoted to randomization and pseudo-randomization (for observational studies) in view of avoiding the effect of possible confounders. An outline of the most common problems and pitfalls, encountered in modelling empirical data, closes the paper, with a warning to be very cautious in modelling and inferring conditional independence between variables. Résumé Le but de cet article est d'offrir une vue d'ensemble sur le thème des relations causales, à partir de la doctrine philosophique aristotélique, et ensuite étendues et formalisées dans le champ de l'analyse statistique multivarée. Dans la revue philosophique on analyse plusieurs conceptions de cause, et les essais de reconnâtre les causes "fausses". La partie centrale du travail s'occupe de modèles causals en forme graphique, qui constituent l'instrument électif de plusieurs recherches causales, et met en evidence la différence entre conditionnement et intervention sur une variable. On a dedié une particulière attention aux procédures de randomization dans le but d'éviter de possible confusions. L'article termine en conseillant d'user de la prudence dans la modelage de l'independence conditionnelle et dans son contrôl empirique. [source] Stability of resting frontal electroencephalogram (EEG) asymmetry and cardiac vagal tone in adolescent females exposed to child maltreatmentDEVELOPMENTAL PSYCHOBIOLOGY, Issue 6 2009Vladimir Miskovic Abstract The experience of child maltreatment is a known risk factor for the development of psychopathology. Structural and functional modifications of neural systems implicated in stress and emotion regulation may provide one mechanism linking early adversity with later outcome. The authors examined two well-documented biological markers of stress vulnerability [resting frontal electroencephalogram (EEG) asymmetry and cardiac vagal tone] in a group of adolescent females exposed to child maltreatment (n,=,38; M age,=,14.47) and their age-matched non-maltreated (n,=,25; M age,=,14.00) peers. Maltreated females exhibited greater relative right frontal EEG activity and lower cardiac vagal tone than controls over a 6-month period. In addition, frontal EEG asymmetry and cardiac vagal tone remained stable in the maltreated group across the 6 months, suggesting that the neurobiological correlates of maltreatment may not simply reflect dynamic, short-term changes but more long lasting alterations. The present findings appear to be the first to demonstrate stability of two biologically based stress-vulnerability measures in a maltreated population. Findings are discussed in terms of plasticity within the neural circuits of emotion regulation during the early childhood period and alternative causal models of developmental psychopathology. © 2009 Wiley Periodicals, Inc. Dev Psychobiol 51: 474,487, 2009 [source] Whither causal models in the neuroscience of ADHD?DEVELOPMENTAL SCIENCE, Issue 2 2005Dave Coghill In this paper we examine the current status of the science of ADHD from a theoretical point of view. While the field has reached the point at which a number of causal models have been proposed, it remains some distance away from demonstrating the viability of such models empirically. We identify a number of existing barriers and make proposals as to the best way for these to be overcome in future studies. These include the need to work across multiple levels of analysis in multidisciplinary teams; the need to recognize the existence of, and then model, causal heterogeneity; the need to integrate environmental and social processes into models of genetic and neurobiological influence; and the need to model developmental processes in a dynamic fashion. Such a model of science, although difficult to achieve, has the potential to provide the sort of framework for programmatic model-based research required if the power and sophistication of new neuroscience technologies are to be effectively exploited. [source] What matters most to prejudice: Big Five personality, Social Dominance Orientation, or Right-Wing Authoritarianism?EUROPEAN JOURNAL OF PERSONALITY, Issue 6 2004Bo Ekehammar Whereas previous research has studied the relation of either (i) personality with prejudice, (ii) personality with social dominance orientation (SDO) and right-wing authoritarianism (RWA), or (iii) SDO and RWA with prejudice, the present research integrates all approaches within the same model. In our study (N,=,183), various causal models of the relationships among the Big Five, SDO, RWA, and Generalized Prejudice are proposed and tested. Generalized Prejudice scores were obtained from a factor analysis of the scores on various prejudice instruments (racism, sexism, prejudice toward homosexuals, and mentally disabled people), which yielded a one-factor solution. The best-fitting causal model, which was our suggested hypothetical model, showed that Big Five personality had no direct effect on Generalized Prejudice but an indirect effect transmitted through RWA and SDO, where RWA seems to capture personality aspects to a greater extent than SDO. Specifically, Generalized Prejudice was affected indirectly by Extraversion, Openness to Experience, and Conscientiousness through RWA, and by Agreeableness through SDO, whereas Neuroticism had no effect at all. The results are discussed against the background of previous research and the personality and social psychology approaches to the study of prejudice. Copyright © 2004 John Wiley & Sons, Ltd. [source] Asynchronous and distributed process improvement: the role of collaborative technologiesINFORMATION SYSTEMS JOURNAL, Issue 2 2001Ned Kock Abstract. The recent proliferation of low-cost computer networks has driven the development of a new type of organization, in which geographical and time constraints to collaboration among process teams have been gradually removed. As these organizations have to cope with a fast pace of change, they rely increasingly on distributed and asynchronous process improvement (PI) groups to redesign their processes. Yet little is known about the effects of asynchronous group support systems (GSSs) on PI groups. We investigate the effects of asynchronous GSSs on PI groups through a two-stage action research study of 38 such groups in three organizations, one in Brazil and two in New Zealand, over 4 years and 4 months. Different PI groups voluntarily conducted all, part or none of their communication through an e-mail conferencing (EC) tool. The research suggests that EC support causes a decrease in the organizational costs associated with PI groups, which, combined with an increase in the number of possible simultaneous PI groups, generates an increase in overall organizational PI efficiency. The research also suggests a neutral overall effect of EC support on PI group outcome quality. Two explanatory causal models summarizing these effects are developed, and implications for research and industry practice are discussed. [source] The Impact of Service User Cognitive Level on Carer Attributions for Aggressive BehaviourJOURNAL OF APPLIED RESEARCH IN INTELLECTUAL DISABILITIES, Issue 3 2002Hannah Tynan Background This study was designed to test the hypothesis that carer attributions for aggressive behaviour vary according to a service user's severity of intellectual disability. Methods Forty-two residential care staff participated in an investigation examining the effects of the level of a service user's intellectual disability on causal attributions for their aggressive behaviour. Equal numbers of participants were assigned to either a ,mild disability' or a ,severe disability' condition and required to read a vignette depicting a service user with aggressive challenging behaviour. The service user's cognitive abilities were experimentally manipulated across conditions, whilst the behaviour described remained unchanged. Participants were required to make attributions along Weiner's (1980) dimensions of locus, stability and controllability, and in accordance with five prominent models of challenging behaviour (Hastings 1997b). Results The service user depicted in the mild disabilities condition was perceived to have significantly greater control over factors causing the aggressive behaviour than the service user in the severe disabilities condition. Participants in the severe disabilities condition considered the aggression to be significantly more challenging. Learned behaviour and emotional causal models of aggressive behaviour were favoured, whilst the physical environment account was seen as least appropriate. Additionally, the biomedical model was rated as significantly more applicable in the severe disability condition than in the mild disability condition. Conclusions Implications for staff and service users are discussed. In particular, the relationship between staff causal attributions for challenging behaviour, their emotional responses and willingness to engage in helping behaviour is explored. [source] Gender differences in science attitude-achievement relationships over time among white middle-school studentsJOURNAL OF RESEARCH IN SCIENCE TEACHING, Issue 4 2002Nancy Mattern Four causal models describing the longitudinal relationships between attitudes and achievement have been proposed in the literature. These models feature: (a) cross-effects over time between attitudes and achievement, (b) influence of achievement predominant over time, (c) influence of attitudes predominant over time, or (d) no cross-effects over time between attitudes and achievement. In an examin-ation of the causal relationships over time between attitudes toward science and science achievement for White rural seventh- and eighth-grade students, the cross-effects model was the best fitting model form for students overall. However, when examined by gender, the no cross-effects model exhibited the most accurate fit for White rural middle-school girls, whereas a new model called the no attitudes-path model exhibited the best fit for these boys. © 2002 Wiley Periodicals Inc. J Res Sci Teach 39: 324,340, 2002 [source] Understanding two-sided persuasion: An empirical assessment of theoretical approachesPSYCHOLOGY & MARKETING, Issue 7 2007Martin EisendArticle first published online: 24 MAY 200 This study tries to evaluate empirically the validity and generality of causal models based on alternative theories and the integrative frame-work provided by Crowley and Hoyer (1994) to explain the underlying persuasive mechanisms of two-sided messages in marketing. In addition to an empirical test of the models, the study theoretically discusses and empirically explores suggestions for model modifications. Applying meta-analytic-based causal estimation, the results show that the parsimonious model based on attribution theory provides high generality and affirms the prevalent use of the theory in previous studies. All other models could be meaningfully improved by integrating alternative processes of less-effortful message elaboration as suggested by dual-process theories. The results suggest that the impact of argument quality in two-sided messages is in line with previous models assuming effortful message elaboration, while less-effortful elaboration processes seem to rely on the number of arguments used in two-sided messages. © 2007 Wiley Periodicals, Inc. [source] Research Review: The importance of callous-unemotional traits for developmental models of aggressive and antisocial behaviorTHE JOURNAL OF CHILD PSYCHOLOGY AND PSYCHIATRY AND ALLIED DISCIPLINES, Issue 4 2008Paul J. Frick The current paper reviews research suggesting that the presence of a callous and unemotional interpersonal style designates an important subgroup of antisocial and aggressive youth. Specifically, callous-unemotional (CU) traits (e.g., lack of guilt, absence of empathy, callous use of others) seem to be relatively stable across childhood and adolescence and they designate a group of youth with a particularly severe, aggressive, and stable pattern of antisocial behavior. Further, antisocial youth with CU traits show a number of distinct emotional, cognitive, and personality characteristics compared to other antisocial youth. These characteristics of youth with CU traits have important implications for causal models of antisocial and aggressive behavior, for methods used to study antisocial youth, and for assessing and treating antisocial and aggressive behavior in children and adolescents. [source] A Causal Model Theory of the Meaning of Cause, Enable, and PreventCOGNITIVE SCIENCE - A MULTIDISCIPLINARY JOURNAL, Issue 1 2009Steven Sloman Abstract The verbs cause, enable, and prevent express beliefs about the way the world works. We offer a theory of their meaning in terms of the structure of those beliefs expressed using qualitative properties of causal models, a graphical framework for representing causal structure. We propose that these verbs refer to a causal model relevant to a discourse and that "A causes B" expresses the belief that the causal model includes a link from A to B. "A enables/allows B" entails that the model includes a link from A to B, that A represents a category of events necessary for B, and that an alternative cause of B exists. "A prevents B" entails that the model includes a link from A to B and that A reduces the likelihood of B. This theory is able to account for the results of four experiments as well as a variety of existing data on human reasoning. [source] | ||||||||||