Assessing theories,Bayes style

The problem addressed in this paper is “the main epistemic problem concerning science”, viz. “the explication of how we compare and evaluate theories [...] in the light of the available evidence” (van Fraassen, BC, 1983, Theory comparison and relevant Evidence. In J. Earman (Ed.), Testing scientific theories (pp. 27–42). Minneapolis: University of Minnesota Press). Sections 1– 3 contain the general plausibility-informativeness theory of theory assessment. In a nutshell, the message is (1) that there are two values a theory should exhibit: truth and informativeness—measured respectively by a truth indicator and a strength indicator; (2) that these two values are conflicting in the sense that the former is a decreasing and the latter an increasing function of the logical strength of the theory to be assessed; and (3) that in assessing a given theory by the available data one should weigh between these two conflicting aspects in such a way that any surplus in informativeness succeeds, if the shortfall in plausibility is small enough. Particular accounts of this general theory arise by inserting particular strength indicators and truth indicators. In Section 4 the theory is spelt out for the Bayesian paradigm of subjective probabilities. It is then compared to incremental Bayesian confirmation theory. Section 4 closes by asking whether it is likely to be lovely. Section 5 discusses a few problems of confirmation theory in the light of the present approach. In particular, it is briefly indicated how the present account gives rise to a new analysis of Hempel’s conditions of adequacy for any relation of confirmation (Hempel, CG, 1945, Studies in the logic of comfirmation. Mind, 54, 1–26, 97–121.), differing from the one Carnap gave in § 87 of his Logical foundations of probability (1962, Chicago: University of Chicago Press). Section 6 adresses the question of justification any theory of theory assessment has to face: why should one stick to theories given high assessment values rather than to any other theories? The answer given by the Bayesian version of the account presented in section 4 is that one should accept theories given high assessment values, because, in the medium run, theory assessment almost surely takes one to the most informative among all true theories when presented separating data. The concluding section 7 continues the comparison between the present account and incremental Bayesian confirmation theory.     

Diachronic Dutch Books and Sleeping Beauty

Hitchcock advances a diachronic Dutch Book argument (DDB) for a 1/3 answer to the Sleeping Beauty problem. Bradley and Leitgeb argue that Hitchcock’s DDB argument fails. We demonstrate the following: (a) Bradley and Leitgeb’s criticism of Hitchcock is unconvincing; (b) nonetheless, there are serious reasons to worry about the success of Hitchcock’s argument; (c) however, it is possible to construct a new DDB for 1/3 about which such worries cannot be raised.     

Mutual Help Groups for Mental Health Problems: A Review of Effectiveness Studies

This paper reviews empirical studies on whether participating in mutual help groups for people with mental health problems leads to improved psychological and social functioning. To be included, studies had to satisfy four sets of criteria, covering: (1) characteristics of the group, (2) target problems, (3) outcome measures, and (4) research design. The 12 studies meeting these criteria provide limited but promising evidence that mutual help groups benefit people with three types of problems: chronic mental illness, depression/anxiety, and bereavement. Seven studies reported positive changes for those attending support groups. The strongest findings come from two randomized trials showing that the outcomes of mutual help groups were equivalent to those of substantially more costly professional interventions. Five of the 12 studies found no differences in mental health outcomes between mutual help group members and non-members; no studies showed evidence of negative effects. There was no indication that mutual help groups were differentially effective for certain types of problems. The studies varied in terms of design quality and reporting of results. More high-quality outcome research is needed to evaluate the effectiveness of mutual help groups across the spectrum of mental health problems.     

Using FMRI to test models of complex cognition

This article investigates the potential of fMRI to test assumptions about different components in models of complex cognitive tasks. If the components of a model can be associated with specific brain regions, one can make predictions for the temporal course of the BOLD response in these regions. An event-locked procedure is described for dealing with temporal variability and bringing model runs and individual data trials into alignment. Statistical methods for testing the model are described that deal with the scan-to-scan correlations in the errors of measurement of the BOLD signal. This approach is illustrated using a "sacrificial" ACT-R model that involves mapping 6 modules onto 6 brain regions in an experiment from Ravizza, Anderson, and Carter (in press) concerned with equation solving. The model's visual encoding predicted the BOLD response in the fusiform gyrus, its controlled retrieval predicted the BOLD response in the lateral inferior prefrontal cortex, and its subgoal setting predicted the BOLD response in the anterior cingulate cortex. On the other hand, its motor programming failed to predict anticipatory activation in the motor cortex, its representational changes failed to predicted the pattern of activity in the posterior parietal cortex, and its procedural component failed to predict an initial spike in caudate. The results illustrate the power of such data to direct the development of a theory of complex problem solving, both at the level of a specific task model as well as at the level of the cognitive architecture.     

生存质量在晚期肿瘤疗效评价中的思考

传统的肿瘤疗效评价方法多采用治愈率、生存率等指标来衡量。随着传统医学模式向生物一心理一社会医学模式转变,生存质量越来越受到重视。生存质量从一个新的角度评价治疗效果,更重视患者的主观感受,而不是仅将临床客观指标作为评价标准,能更客观地指导治疗方案的选择。     

干扰素治疗慢性乙型肝炎临床评价

干扰素治疗慢性乙型肝炎已有20多年历史,由于其抑制病毒复制和强大的免疫调节作用,以及具有疗程确定,不引起病毒变异耐药,显效后疗效持久的特点,是慢性乙型肝炎抗病毒治疗的首选药物之一。多项试验证明聚乙二醇化干扰素治疗慢性乙型肝炎的疗效优于普通干扰素和核苷类似物。本文就有关干扰素单用、联合核苷类似物和序贯疗法治疗慢性乙型肝炎的临床研究和HBV基因型对干扰素疗效的影响做简要综述。     

医院临床药学管理要注重药物经济学评价与研究

通过对医院临床药学管理的药物经济学评价与研究的重要性、药物经济学评价与研究的基本方法和技术的论述,提出在进行临床药学管理的同时,应注重和开展药物经济学评价与研究,使之成为医院临床药学管理重要方面。目前医院临床药物管理中需关注的评价与研究项目,包括医院药品费用评价和控制研究、医院用药目录评价和规范医生行为研究、药物的适用范围评价与科学合理性研究、患者选择药物行为评价和正确帮助择药研究。     

Caregiver Involvement in the Intensive Mental Health Program: Influence on Changes in Child Functioning

We examined behavioral markers of caregiver involvement and the ways in which family participation was related to treatment outcomes in 47 elementary school children with SED enrolled in a school-based intensive mental health program. Measures of caregiver involvement included therapeutic home visits, attendance at therapeutic meetings, completion of ratings on the daily point sheet, and extra communications with the therapeutic team on the point sheet. Greater initial impairment was associated with greater caregiver involvement. Greater caregiver involvement was linked to improvement in child thought processes, increased ability to provide emotional and social supports for the child, and greater overall child functioning at discharge. Our findings also reflected increased therapists’ attempts to provide additional in-home services in cases where caregivers demonstrated a decline in their ability to provide for their children’s physical and material needs, or in which therapists discovered that the family functioning was more impaired than what was initially assessed. We provide a case study that exemplifies many of these findings.     

How Berkeley Corrupted His Capacity to Conceive

Berkeley’s capacity to conceive of mind-independent bodies was corrupted by his theory of representation. He thought that representation of things outside the mind depended on resemblance. Since ideas can resemble nothing than ideas, and all ideas are mind dependent, he concluded that we couldn’t form ideas of mind-independent bodies. More generally, he thought that we had no inner resembling proxies for mind-independent bodies, and so we couldn’t even form a notion of such things. Because conception is a suggestible faculty, Berkeley’s arguments actually made it the case that he himself couldn’t conceive of mind-independent bodies.

Challenges of Evaluating Multilevel Interventions

This article uses the Comprehensive Mixed-Methods Participatory Evaluation (CMMPE; Nastasi and Hitchcock Transforming school mental health services: Population-based approaches to promoting the competency and wellness of children, Thousand Oaks, CA: Corwin Press with National Association of School Psychologists 2008; Nastasi et al. School-based mental health services: creating comprehensive and culturally specific programs. Washington, DC: American Psychological Association 2004) model as a framework for addressing the multiplicity of evaluation decisions and complex nature of questions related to program success in multilevel interventions. CMMPE defines program success in terms of acceptability, integrity, social or cultural validity, outcomes (impact), sustainability and institutionalization, thus broadening the traditional notions of program outcomes. The authors use CMMPE and an example of a community-based multilevel sexual risk prevention program with multiple outcomes to discuss challenges of evaluating multilevel interventions. The sexual risk program exemplifies what Schensul and Tricket (this issue) characterize as multilevel intervention–multilevel evaluation (M–M), with both intervention and evaluation at community, health practitioner, and patient levels. The illustration provides the context for considering several challenges related to M–M designs: feasibility of randomized controlled trials within community-based multilevel intervention; acceptability and social or cultural validity of evaluation procedures; implementer, recipient, and contextual variations in program success; interactions among levels of the intervention; unanticipated changes or conditions; multiple indicators of program success; engaging multiple stakeholders in a participatory process; and evaluating sustainability and institutionalization. The complexity of multilevel intervention and evaluation designs challenges traditional notions of evaluation research and experimental designs. Overcoming these challenges is critical to effective translation of research to practice in psychology and related disciplines.