A Comparison of Psychopathic Trait Latent Profiles in Service Members

This study used latent profile analysis (LPA) to identify differing classes of psychopathic traits in a large sample of military personnel (90.7% Army National Guard) and examined how membership across profiles can be differentiated by mean scores on external correlates relevant to psychopathy and/or to military service (e.g., aggression, posttraumatic stress symptoms, impulsivity). Psychopathy was operationalized via the three-factor model of the Levenson Self-Report Psychopathy Scales (LSRP; Brinkley et al. 2008; Levenson et al. 1995). LPA revealed optimal fit for a four-profile solution. Three profiles had roughly equivalent within-profile means across the three factors, characterized by below average, average, and above/high average LSRP scores. The fourth profile emerged as qualitatively different: high on LSRP-Callous but below average on LSRP-Egocentricity and LSRP-Antisocial. The four profiles were differentiable based on their mean scores on external correlates, suggesting varied implications for externalizing and internalizing features across psychopathic trait configurations in a military sample. Implications for studying psychopathy in military and other novel samples are discussed.

     

Opposing powers

A disposition mask is something that prevents a disposition from manifesting despite the occurrence of that disposition’s characteristic stimulus, and without eliminating that disposition. Several authors have maintained that masks must be things extrinsic to the objects that have the masked dispositions. Here it is argued that this is not so; masks can be intrinsic to the objects whose dispositions they mask. If that is correct, then a recent attempt to distinguish dispositional properties from so-called categorical properties fails.     

A decision model for steady-state choice in concurrent chains

Grace and McLean (2006) proposed a decision model for acquisition of choice in concurrent chains which assumes that after reinforcement in a terminal link, subjects make a discrimination whether the preceding reinforcer delay was short or long relative to a criterion. Their model was subsequently extended by Christensen and Grace (2008, 2009a, 2009b) to include effects of initial- and terminal-link duration on choice. We show that an expression for steady-state responding can be derived from the decision model, which enables a model for choice that provides an account of archival data that is equal or superior to the contextual choice model (Grace, 1994) and hyperbolic value-added model (Mazur, 2001) in terms of goodness of fit, parsimony, and parameter invariance. The success of the steady-state decision model validates the strategy of understanding acquisition phenomena as a bridge toward explaining choice at the molar level.