Recent Submissions

  • Power of source as a factor in deontic inference

    Kilpatrick, S.G.; Manktelow, Ken I.; Over, D.E. (Taylor & Francis, 2007)
    Power has been studied in various guises in both the social cognition and the reasoning literatures. In this paper, three experiments are reported in which this factor was investigated in the domain of deontic thinking. Power of source of deontic statements was varied within several scenarios, and participants judged the degree to which they thought an injunction would be carried out. In the first experiment, permission statements were used, and it was found that, as predicted, power was positively related to degree of endorsement of deontic conclusions across scenarios. In the second experiment, these findings were generalised across three further deontic domains (threat, warning, and promise) and two different syntactic forms (conjunctive and disjunctive). In the third experiment, the hypothesis that power effects were mediated by subjective judgements of conditional probability was investigated and confirmed. It is argued that these results favour theories that give a general role to probabilistic factors, rather than those based on domain-specific
  • Influence of language background on tests of cognitive abilities: Australian data

    Carstairs, Jane R.; Myors, Brett; Shores, E. Arthur; Fogarty, Gerard (Taylor & Francis, 2006)
    This study examines the effect of language background on the performance of healthy participants on a battery of cognitive measures. The study was conducted as part of a larger normative study: the Macquarie University Neuropsychological Normative Study (MUNNS). A comparison was made between the test performance of three language background groups: participants from a non-English-speaking background whose first language was other than English (NESB-OE, N = 42); participants from a non-English-speaking background whose first language was English (NESB-E, N = 34); and participants from an English-speaking background (ESB, N = 40). A number of tests used in clinical neuropsychological assessment were found to be sensitive to the background of the participant, and trends in the data suggest that two factors are operating independently. It is proposed that one factor is language or proficiency in English that impacts on verbal subtests and the other is a sociocultural factor that impacts on performance or nonverbal subtests. These findings question current practices when assessing people from non-English-speaking backgrounds.
  • Accuracy of percentile judgments used in the utility analysis of personnel selection procedures

    Myors, Brett; Carstairs, Jane R.; Todorov, Natasha (Taylor & Francis, 2002)
    Schmidt, Hunter, McKenzie and Muldrow's (1979) global estimation procedure for determining the standard deviation of job performance in monetary terms (SDy) is based on the assumption that people are able to estimate the percentiles of a normal distribution. The aim of the research reported here was to test the veracity of this assumption. We used participants who were primed to work with percentiles on a task that provided all the information necessary to solve the problem. Participants' percentile estimates were found to be grossly in error, suggesting that utilities estimated by the Schmidt et al. procedure are inaccurate. This finding was replicated in a second study which also examined the effect of group decision-making on the estimation process. Group estimates were found to be no better than individual estimates
  • Factorial invariance for combined Wechsler Adult Intelligence Scale-Revised and Wechsler Memory Scale-Revised scores in a sample of clients with alcohol dependency.

    Bowden, Stephen C.; Ritter, Alison J.; Carstairs, Jane R.; Shores, E. Arthur; Pead, J.; Greeley, Janet D.; Whelan, Gregory; Long, Caroline M.; Clifford, Christine C. (Psychology Press (Taylor & Francis), 2001)
    This study examined the joint factor structure of the WAIS-R and WMS-R in a sample of 289 participants (mostly males) with alcohol dependency. In a confirmatory phase we contrasted a range of factor models derived from previous analyses of the Wechsler scales. The best fitting model incorporated five factors representing Verbal Comprehension, Perceptual Organization, Attention-Concentration, Verbal Memory, and Visual Memory, with reassignment of factor loadings for two subtests. The invariance of the measurement model was then examined comparing data from a large sample of healthy participants (J. R. Carstairs & E. A. Shores, 1999). The results indicated that the number of factors was invariant across samples, and four of the factors satisfied the criterion of partial measurement invariance.
  • Raised salivary testosterone in women is associated with increased attraction to masculine faces.

    Welling, L.L.M.; Jones, B.C.; DeBruine, L.M.; Conway, C.A.; Law Smith, M.J.; Little, A.C.; Feinberg, D.R.; Sharp, Martin A.; Al-Dujaili, E.A.S. (Elsevier Science Direct, 2007)
    Women's preferences for masculinity in men's faces, voices and behavioral displays change during the menstrual cycle and are strongest around ovulation. While previous findings suggest that change in progesterone level is an important hormonal mechanism for such variation, it is likely that changes in the levels of other hormones will also contribute to cyclic variation in masculinity preferences. Here we compared women's preferences for masculine faces at two points in the menstrual cycle where women differed in salivary testosterone, but not in salivary progesterone or estrogen. Preferences for masculinity were strongest when women's testosterone levels were relatively high. Our findings complement those from previous studies that show systematic variation in masculinity preferences during the menstrual cycle and suggest that change in testosterone level may play an important role in cyclic shifts in women's preferences for masculine traits.
  • Salience of emotional displays of danger and contagion in faces is enhanced when progesterone levels are raised.

    Conway, C.A.; Jones, B.C.; DeBruine, L.M.; Welling, L.L.M.; Law Smith, M.J.; Perrett, D.I.; Sharp, Martin A.; Al-Dujaili, E.A.S. (Elsevier Science Direct, 2007)
    Findings from previous studies of hormone-mediated behavior in women suggest that raised progesterone level increases the probability of behaviors that will reduce the likelihood of disruption to fetal development during pregnancy (e.g. increased avoidance of sources of contagion). Here, we tested women's (N=52) sensitivity to potential cues to nearby sources of contagion (disgusted facial expressions with averted gaze) and nearby physical threat (fearful facial expressions with averted gaze) at two points in the menstrual cycle differing in progesterone level. Women demonstrated a greater tendency to perceive fearful and disgusted expressions with averted gaze as more intense than those with direct gaze when their progesterone level was relatively high. By contrast, change in progesterone level was not associated with any change in perceptions of happy expressions with direct and averted gaze, indicating that our findings for disgusted and fearful expressions were not due to a general response bias. Collectively, our findings suggest women are more sensitive to facial cues signalling nearby contagion and physical threat when raised progesterone level prepares the body for pregnancy.
  • Subclinical delusional ideation and a self-reference bias in everyday reasoning.

    Galbraith, Niall; Manktelow, Ken I.; Morris, Neil (British Psychological Society, 2008)
    Previous studies (e.g. Moller & Husby, 2000; Blackwood et al., 2004) have revealed that delusional thinking is accompanied by an exaggerated focus upon the self and upon stimuli that are perceived to be related to the self. The objective was to examine whether those high in subclinical delusional ideation exhibit a heightened tendency for self-reference. Using a mixed design, healthy individuals, classified into high- and low-scoring groups on the Peters et al. Delusions Inventory (Peters, Day, & Garety, 1996), were compared on everyday reasoning tasks across three experiments. High-PDI scorers, in contrast to the low-PDI group, rated self-referent objections to everyday arguments as stronger than other-referent objections and formulated more self-referent assertion-based objections to everyday arguments. The findings support the notion that subclinical delusional ideation is linked to a self-reference bias, which is evident in the sort of everyday thinking that people engage in when forming or evaluating their beliefs and which may contribute to delusion formation.
  • Conditions for the acceptance of deontic conditionals.

    Over, D.E.; Manktelow, Ken I.; Hadjichristidis, C. (American Psychological Association, 2004)
    Recent psychological research has investigated how people assess the probability of an indicative conditional. Most people give the conditional probability of q given p as the probability of if p then q. Asking about the probability of an indicative conditional, one is in effect asking about its acceptability. But on what basis are deontic conditionals judged to be acceptable or unacceptable? Using a decision theoretic analysis, we argue that a deontic conditional, of the form if p then must q or if p then may q, will be judged acceptable to the extent that the p & q possibility is preferred to the p & not-q possibility. Two experiments are reported in which this prediction was upheld. There was also evidence that the pragmatic suitability of permission rules is partly determined by evaluations of the not-p & q possibility. Implications of these results for theories of deontic reasoning are discussed.
  • Measurement invariance of core cognitive abilities in heterogenous neurological and community samples.

    Bowden, Stephen C.; Cook, Mark J.; Bardenhagen, Fiona J.; Shores, E. Arthur; Carstairs, Jane R. (Elsevier, 2004)
    Confirmatory factor analysis of Australian adaptations of combined Wechsler Adult Intelligence Scale-Revised (WAIS-R) and Wechsler Memory Scale-Revised (WMS-R) scores was conducted in a sample of 277 participants undergoing investigation for neurological disorders. The best-fitting model was a six-factor model representing the latent abilities of Verbal Comprehension, Perceptual Organization, Working Memory, Verbal Memory, Visual Memory, and Processing Speed. Invariance of the measurement model was then examined in the mean and covariance structure with data from a recent Australian normative study of the WAIS-R and WMS-R. [Carstairs J.R. & Shores E.A.Aust Psychol 35 (2000) 36-40]. Results suggest that the measurement model underlying test scores displayed “strong” metric invariance [Widaman, K. F., & Reise, S. P. (1997). Exploring the measurement invariance of psychological instruments: Applications in the substance abuse domain. In K. J. Bryant & M. Windle (Eds.), The science of prevention: Methodological advance from alcohol and substance abuse research (pp. 281–324). Washington, DC: American Psychological Association] across clinical and community samples. These findings satisfy assumptions necessary for uncomplicated interpretation of validity correlations and differences in test scores across groups.
  • Can subthreshold summation be observed with the Ehrenstein illusion?

    Salvano-Pardieu, Veronique; Taliercio, Alain; Manktelow, Ken I.; Meigen, Thomas; Wink, Brian (Pion, 2006)
    Subthreshold summation between physical target lines and illusory contours induced by edges such as those produced in the Kanizsa illusion has been reported in previous studies. Here, we investigated the ability of line-induced illusory contours, using Ehrenstein figures, to produce similar subthreshold summation. In the first experiment, three stimulus conditions were presented. The target line was superimposed on the illusory contour of a four-arm Ehrenstein figure, or the target was presented between two dots (which replaced the arms of the Ehrenstein figure), or the target was presented on an otherwise blank screen (control). Detection of the target line was significantly worse when presented on the illusory contour (on the Ehrenstein figure) than when presented between two dots. This result was consistent for both curved and straight target lines, as well as for a 100 ms presentation duration and unlimited presentation duration. Performance was worst in the control condition. The results for the three stimulus conditions were replicated in a second experiment in which an eight-arm Ehrenstein figure was used to produce a stronger and less ambiguous illusory contour. In the third experiment, the target was either superimposed on the illusory contour, or was located across the central gap (illusory surface) of the Ehrenstein figure, collinear with two arms of the figure. As in the first two experiments, the target was either presented on the Ehrenstein figure, or between dots, or on a blank screen. Detection was better in the dot condition than in the Ehrenstein condition, regardless of whether the target was presented on the illusory contour or collinear with the arms of the Ehrenstein figure. These three experiments demonstrate the ability of reduced spatial uncertainty to facilitate the detection of a target line, but do not provide any evidence for subthreshold summation between a physical target line and the illusory contours produced by an Ehrenstein figure. The incongruence of these results with previous findings on Kanizsa figures is discussed.