The perils of tweaking: how to use macrodata to set parameters in complex simulation models

When can macroscopic data about a system be used to set parameters in a microfoundational simulation? We examine the epistemic viability of tweaking parameter values to generate a better fit between the outcome of a simulation and the available observational data. We restrict our focus to microfoundational simulations—those simulations that attempt to replicate the macrobehavior of a target system by modeling interactions between microentities. We argue that tweaking can be effective but that there are two central risks. First, tweaking risks overfitting the simulation to the data and thus compromising predictive accuracy; and second, it risks compromising the microfoundationality of the simulation. We evaluate standard responses to tweaking and propose strategies to guard against these risks.     

The relationship between psychopathic features, violence and treatment outcome: the comparison of three youth measures of psychopathic features

Few studies have compared self-report and clinician-administered measures of youth psychopathic features in juvenile-justice settings in terms of antisocial behavior and treatment indices. In a sample of 85 adjudicated delinquents, the predictive validities of the Antisocial Process Screening Device (APSD), the modified Childhood Psychopathy Scale (mCPS), and the Hare Psychopathy Checklist: Youth Version (PCL:YV) were tested. Three indices of institutional antisocial behavior (physical aggression; verbal aggression; administrative infractions) and two indices of treatment progress (time to treatment level promotion; whether treatment levels were dropped) were used as external correlates. The self-report measures (mCPS more so than APSD) were more consistently and strongly related to antisocial behavior and to the days required to progress in treatment than the PCL:YV. The following issues are discussed: (i) implications of the potential impact of measurement format on the understanding and predictive validity of youth psychopathy features and measures; (ii) the differential predictive validity of self-report versus clinician-administered measures; and (iii) the potential practical utility of measures of psychopathic features in youth.     

Two different biological configurations for long-term memory

Long-term memory (LTM) in Hermissenda can be distinguished from consolidated long-term memory (CLTM) by determining how long recall is retained. LTM is retained for approximately 1 day, while CLTM is retained for at least 3 days. During the transition from LTM to CLTM, the extent of retention appears to depend partially on how much consolidation has been completed. Several models are discussed that may be related to the two different manifestations of recall.     

Response to commentary on the multimodal treatment study of ADHD (MTA): mining the meaning of the MTA

In the December 2000 issue of the Journal of Abnormal Child Psychology, we published a set of papers presenting secondary analyses of the Multimodal Treatment Study of ADHD (MTA), and R. A. Barkley (2000) provided a commentary. A critique of the design of the study (MTA Cooperative Group, 1999) was presented based on a theoretical perspective of a behavioral inhibition deficit that has been hypothesized as the core deficit of ADHD (R. A. Barkley, 1997). The commentary questioned the design and analysis of the MTA in terms of (1) the empirical criteria for selection of components of behavioral (Beh) intervention, (2) the effectiveness of the Beh intervention, (3) the methods for analyses at the group and individual level, (4) implications of the MTA findings for clinical practice, (5) the role of genetics in response to treatment, and (6) the lack of a nontreatment control group. In this response, we relate the content of the papers to the commentary, (1) by reviewing the selection criteria for the Beh treatment, as outlined by K. C. Wells, W. E. Pelham, et al. (2000), (2) by addressing the myth that the MTA Beh treatment was ineffective (Pelham, 1999), (3) by describing the use of analyses at the level of the individual participant, as presented by J. S. March et al. (2000) and W. E. Pelham et al. (2000) as well as elsewhere by J. M. Swanson et al. (2001) and C. K. Conners et al. (2001), (4) by relating some of the suggestions from the secondary analyses about clinically relevant factors such as comorbidity (as presented by J. S. March et al., 2000) and family and parental characteristics (as presented by B. Hoza et al., 2000, S. P. Hinshaw et al., 2000, and K. C. Wells, J. N. Epstein, et al., 2000), (5) by discussing the statistical concept of heritability and the lack of a significant difference in the presence of ADHD symptoms in parents of the MTA families compared to parents in the classmate-control families (as presented by J. N. Epstein, et al., 2000), and (6) by acknowledging that an ethically necessary weakness of the MTA design is that it did not include a no-treatment control group. We discuss the use of secondary analyses to suggest how, when, and for what subgroups effectiveness of the Beh treatment may have been manifested. Finally, we invite others to use the large and rich data set that will soon be available in the public domain, to perform secondary analyses to mine the meaning of the MTA and to evaluate theories of ADHD and response to treatments.     

Cognitive marital therapy

This article reviews recent applications of cognitive therapy to the treatment of marital distress. Three categories of cognitive phenomena that can decrease marital satisfaction and elicit dysfunctional interactions between spouses are described. First, automatic thoughts that comprise an individual's stream-of-consciousness thinking about marital events can be biased by systematic cognitive distortions. Inaccurate attributions about the causes of marital problems are a major form of such automatic thoughts. Second, individuals' behaviors toward their partners are influenced by their expectancies about the probabilities of the partner's subsequent responses, and these expectancies also are susceptible to systematic distortion. Third, an individual's unrealistic or irrational beliefs about the nature of intimate relationships can produce distress and dysfunctional behavioral responses toward the partner. Methods for assessing and modifying these dysfunctional cognitions, particularly in conjoint treatment, are described. Similarities and differences between cognitive therapy and rational-emotive therapy in the treatment of marital problems are noted.     

Perception of slant-in-depth is automatic

Two experiments assessed perception of the slant-in-depth of static irregularly contoured shapes when attention was withdrawn from processing slant-in-depth. The experiments showed that when the memory load of the experimental task is minimal, discrimination of slant-in-depth is evidenced even when attention has not been directed to slant discrimination. The findings are brought to bear on a model of perceiving shape-at-a-slant (Epstein & Lovitts, 1985) that partitions the components of the process into automatic and attention-demanding operations.     

An aerosol spray alternative to cigarette smoking in the study of the behavioral and physiological effects of nicotine

For studies of the behavioral and physiological effects of nicotine in smokers, delivery of nicotine via cigarette smoking is highly variable and difficult to control. A more precise method of delivery is needed in order to accurately manipulate the amount of nicotine being presented and, thus, to determine its quantitative effects. The objective of the study reported here was to test an aerosol nasal-spray method of delivering measured doses of nicotine. Eleven healthy males were presented 0 mg (placebo), 0.5 mg, 1.0 mg, and 2.0 mg of nicotine over 5 min during four separate sessions, and changes were observed in plasma nicotine concentration and cardiovascular activity. Dose-response relationships were observed between nicotine presented via this method and plasma nicotine, heart rate, systolic blood pressure, and, to a lesser extent, diastolic blood pressure. These results suggest that this aerosol spray method of presenting nicotine provides the measured doses necessary for quantification of nicotine’s effects.     

The spontaneous interconnection of four repertoires of behavior in a pigeon (Columba livia)

A pigeon was trained to peck a small facsimile of a banana placed within its reach, to climb onto a box, to open a door, and to push a box toward targets. When confronted with a new situation-the banana was placed out of reach, and the box was placed behind the door-the four repertoires came together rapidly to produce a humanlike solution to the problem. A tentative account of the performance is offered in terms of empirically validated principles.