A one-way random effects model for trimmed means

The random effects ANOVA model plays an important role in many psychological studies, but the usual model suffers from at least two serious problems. The first is that even under normality, violating the assumption of equal variances can have serious consequences in terms of Type I errors or significance levels, and it can affect power as well. The second and perhaps more serious concern is that even slight departures from normality can result in a substantial loss of power when testing hypotheses. Jeyaratnam and Othman (1985) proposed a method for handling unequal variances, under the assumption of normality, but no results were given on how their procedure performs when distributions are nonnormal. A secondary goal in this paper is to address this issue via simulations. As will be seen, problems arise with both Type I errors and power. Another secondary goal is to provide new simulation results on the Rust-Fligner modification of the Kruskal-Wallis test. The primary goal is to propose a generalization of the usual random effects model based on trimmed means. The resulting test of no differences among J randomly sampled groups has certain advantages in terms of Type I errors, and it can yield substantial gains in power when distributions have heavy tails and outliers. This last feature is very important in applied work because recent investigations indicate that heavy-tailed distributions are common. Included is a suggestion for a heteroscedastic Winsorized analog of the usual intraclass correlation coefficient.     

COGNITIVE RESTRUCTURING AND MENTAL CONTAMINATION: AN EMPIRICAL RE-CONCEPTUALIZATION

The main goal of this article is to propose a cognitive technology for blocking the impact of mental contamination during cognitive restructuring in cognitive-behavioral and rational-emotive therapy, by using fundamental research findings from cognitive psychology. In step 1, after a review of the relevant cognitive and social psychology literature, the authors elaborated several techniques hypothesized to control mental contamination. In step 2—Experiment I—the authors tested the efficacy of these techniques in blocking mental contamination. The three techniques that proved to be effective in controlling mental contamination were: (a) the global restructuring technique; (b) the rational anticipation technique; (c) the incompatible information technique. In step 3—Experiment II—these techniques were adapted and tested in clinical setting using a single case experiment design-multiple baselines across subjects (five subjects with simple phobia). The techniques were shown to be effective in both stimulating the assimilation of new adaptive cognitions (i.e., global restructuring and incompatible information technique) and in preventing relapse (i.e., rational anticipation technique). Future directions for research are discussed. Address correspondence to Daniel David, Ph.D., Department of Psychology and Center for Cognitive and Behavioral Psychotherapies, Babes-Bolyai University, No. 37, Gh. Bilascu Street, 3400, Cluj-Napoca, Cluj, Romania; e-mail: danieldavid@psychology.ro.     

Beyond Positivist Ecology: Toward an Integrated Ecological Ethics

A post-positivist understanding of ecological science and the call for an “ecological ethic” indicate the need for a radically new approach to evaluating environmental change. The positivist view of science cannot capture the essence of environmental sciences because the recent work of “reflexive” ecological modelers shows that this requires a reconceptualization of the way in which values and ecological models interact in scientific process. Reflexive modelers are ecological modelers who believe it is appropriate for ecologists to examine the motives for their choices in developing models; this self-reflexive approach opens the door to a new way of integrating values into public discourse and to a more comprehensive approach to evaluating ecological change. This reflexive building of ecological models is introduced through the transformative simile of Aldo Leopold, which shows that learning to “think like a mountain” involves a shift in both ecological modeling and in values and responsibility. An adequate, interdisciplinary approach to ecological valuation, requires a re-framing of the evaluation questions in entirely new ways, i.e., a review of the current status of interdisciplinary value theory with respect to ecological values reveals that neither of the widely accepted theories of environmental value—neither economic utilitarianism nor intrinsic value theory (environmental ethics)—provides a foundation for an ecologically sensitive evaluation process. Thus, a new, ecologically sensitive, and more comprehensive approach to evaluating ecological change would include an examination of the metaphors that motivate the models used to describe environmental change.

Consenting to uncertainty: challenges for informed consent to disease screening—a case study

This paper uses chronic beryllium disease as a case study to explore some of the challenges for decision-making and some of the problems for obtaining meaningful informed consent when the interpretation of screening results is complicated by their probabilistic nature and is clouded by empirical uncertainty. Although avoidance of further beryllium exposure might seem prudent for any individual whose test results suggest heightened disease risk, we will argue that such a clinical precautionary approach is likely to be a mistake. Instead, advice on the interpretation of screening results must focus not on risk per se, but on avoidable risk, and must be carefully tailored to the individual. These points are of importance for individual decision-making, for informed consent, and for occupational health.

Regression in Autistic Spectrum Disorders

A significant proportion of children diagnosed with Autistic Spectrum Disorder experience a developmental regression characterized by a loss of previously-acquired skills. This may involve a loss of speech or social responsitivity, but often entails both. This paper critically reviews the phenomena of regression in autistic spectrum disorders, highlighting the characteristics of regression, age of onset, temporal course, and long-term outcome. Important considerations for diagnosis are discussed and multiple etiological factors currently hypothesized to underlie the phenomenon are reviewed. It is argued that regressive autistic spectrum disorders can be conceptualized on a spectrum with other regressive disorders that may share common pathophysiological features. The implications of this viewpoint are discussed.     

Suffering, Sympathy, and (Environmental) Security: Reassessing Rorty’s Contribution to Human Rights Theory

This article reassess Rorty’s contribution to human rights theory. It addresses two key questions: (1) Does Rorty sustain his claim that there are no morally relevant transcultural facts? (2) Does Rorty’s proposed sentimental education offer an adequate response to contemporary human rights challenges? Although both questions are answered in the negative, it is argued here that Rorty’s focus on suffering, sympathy, and security, offer valuable resources to human rights theorists. The article concludes by considering the idea of a dual approach to human rights, combining Rorty’s emphasis on sentiment with an analysis of patterns of responsibility for the underfulfilment of human rights.     

Repeated cocaine experience facilitates sucrose-reinforced operant responding in enriched and isolated rats

The purpose of the present experiment was to determine whether repeated cocaine exposure differentially affects sucrose-reinforced operant responding in rats raised in an enriched condition (EC) or an isolated condition (IC). Specifically, the performance of EC and IC rats pressing a lever for sucrose under a high fixed-ratio schedule (FR 30) prior to and after 10 days of exposure to cocaine (15 mg/kg, i.p.) or saline was compared. Regardless of rearing condition, rats repeatedly exposed to cocaine had shorter reacquisition latencies to complete a sucrose-reinforced FR 30 task than saline controls. The results suggest that cocaine exposure may have cross-sensitized both EC and IC rats to the reinforcing effects of sucrose or sucrose-associated cues, thus facilitating reacquisition of operant responding.     

Etiologic Subtypes of Attention-Deficit/Hyperactivity Disorder: Brain Imaging, Molecular Genetic and Environmental Factors and the Dopamine Hypothesis

Multiple theories of Attention-Deficit/Hyper- activity Disorder (ADHD) have been proposed, but one that has stood the test of time is the dopamine deficit theory. We review the narrow literature from recent brain imaging and molecular genetic studies that has improved our understanding of the role of dopamine in manifestation of symptoms of ADHD, performance deficits on neuropsychological tasks, and response to stimulant medication that constitutes the most common treatment of this disorder. First, we consider evidence of the presence of dopamine deficits based on the recent literature that (1) confirms abnormalities in dopamine-modulated frontal-striatal circuits, reflected by size (smaller-than-average components) and function (hypoactivation); (2) clarifies the agonist effects of stimulant medication on dopaminergic mechanisms at the synaptic and circuit level of analysis; and (3) challenges the most-widely accepted ADHD-related neural abnormality in the dopamine system (higher-than-normal dopamine transporter [DAT] density). Second, we discuss possible genetic etiologies of dopamine deficits based on recent molecular genetic literature, including (1) multiple replications that confirm the association of ADHD with candidate genes related to the dopamine receptor D4 (DRD4) and the DAT; (2) replication of differences in performance of neuropsychological tasks as a function of the DRD4 genotype; and (3) multiple genome-wide linkage scans that demonstrate the limitations of this method when applied to complex disorders but implicate additional genes that may contribute to the genetic basis of ADHD. Third, we review possible environmental etiologies of dopamine deficits based on recent studies of (1) toxic substances that may affect the dopamine system in early development and contribute substantially to the etiology of ADHD; (2) fetal adaptations in dopamine systems in response to stress that may alter early development with lasting effects, as proposed by the developmental origins of health and disease hypothesis; and (3) gene-environment interactions that may moderate selective damage or adaptation of dopamine neurons. Based on these reviews, we identify critical issues about etiologic subtypes of ADHD that may involve dopamine, discuss methods that could be used to address these issues, and review old and new theories that may direct research in this area in the future.     

Attention-Deficit/Hyperactivity Disorder: A Neuropsychological Perspective Towards DSM-V

Neuropsychological methods and techniques have much to offer in the evaluation of the individual suspected as having Attention-Deficit/Hyperactivity Disorder (ADHD). After a review of the historical evolution of the ADHD concept, incidence and prevalence, and DSM-IV criteria for diagnosis, especially as regards omission related to gender differences, and other associated cultural, familial, socioenvironmental, and subject influences, this paper describes a number of dilemmas and obstacles encountered in clinical practice. Included are the confounds associated with the wide range of possible comorbidities, the insufficiency of current DSM-IV criteria, the emergence of subtype differentiation and its impact on diagnosis and treatment. The complex relationship between neuropsychological constructs and ADHD, and obstacles to valid assessment are also addressed. The complexities associated with a thorough ADHD evaluation are viewed within an impressive and expansive existing scientific framework and recommendations are made for future directions.     

大学生群体中价值观、感知环境质量与环境意识的关系研究

本研究利用一项大学生环境意识调查数据,探讨了价值观、感知环境质量和环境意识之间关系,并对英格尔哈特的“客观问题和主观价值”假设进行检验。研究结果基本支持该假设,后物质主义者比物质主义者的环境意识更强,感知环境质量差者比感知环境质量好者的环境意识更强。此外,研究还发现,感知环境质量比价值观对大学生的环境意识作用更强;感知中国环境质量比感知家乡环境质量对大学生的环境意识作用更强。