New Foundations for a Relational Theory of Theory-revision

AGM-theory, named after its founders Carlos Alchourrón, Peter Gärdenfors and David Makinson, is the leading contemporary paradigm in the theory of belief-revision. The theory is reformulated here so as to deal with the central relational notions ‘J is a contraction of K with respect to A’ and ‘J is a revision of K with respect to A’. The new theory is based on a principal-case analysis of the domains of definition of the three main kinds of theory-change (expansion, contraction and revision). The new theory is stated by means of introduction and elimination rules for the relational notions. In this new setting one can re-examine the relationship between contraction and revision, using the appropriate versions of the so-called Levi and Harper identities. Among the positive results are the following. One can derive the extensionality of contraction and revision, rather than merely postulating it. Moreover, one can demonstrate the existence of revision-functions satisfying a principle of monotonicity. The full set of AGM-postulates for revision-functions allow for completely bizarre revisions. This motivates a Principle of Minimal Bloating, which needs to be stated as a separate postulate for revision. Moreover, contractions obtained in the usual way from the bizarre revisions, by using the Harper identity, satisfy Recovery. This provides a new reason (in addition to several others already adduced in the literature) for thinking that the contraction postulate of Recovery fails to capture the Principle of Minimal Mutilation. So the search is still on for a proper explication of the notion of minimal mutilation, to do service in both the theory of contraction and the theory of revision. The new relational formulation of AGM-theory, based on principal-case analysis, shares with the original, functional form of AGM-theory the idealizing assumption that the belief-sets of rational agents are to be modelled as consistent, logically closed sets of sentences. The upshot of the results presented here is that the new relational theory does a better job of making important matters clear than does the original functional theory. A new setting has been provided within which one can profitably address two pressing questions for AGM-theory: (1) how is the notion of minimal mutilation (by both contractions and revisions) best analyzed? and (2) how is one to rule out unnecessary bloating by revisions?     

A new secretary problem with rank-based selection and cardinal payoffs

We present an extension of the secretary problem in which the decision maker (DM) sequentially observes up to n applicants whose values are random variables X₁,X₂,…,X_n drawn i.i.d. from a uniform distribution on [0,1]. The DM must select exactly one applicant, cannot recall released applicants, and receives a payoff of x_t, the realization of X_t, for selecting the tth applicant. For each encountered applicant, the DM only learns whether the applicant is the best so far. We prove that the optimal policy dictates skipping the first sqrt(n)-1 applicants, and then selecting the next encountered applicant whose value is a maximum.     

Are members of low status groups perceived as bad, or badly off? Egalitarian negative associations and automatic prejudice

Three studies explored the hypothesis that implicit measures of prejudice can tap negative, yet egalitarian associations. In Study 1, automatically associating African Americans with oppression predicted greater automatic prejudice. In Studies 2 and 3, classically conditioning associations between the novel group Noffians and words like oppressed, maltreated, and victimized led to greater automatic prejudice against Noffians. Results suggest that White Americans’ negative automatic associations with African Americans may partly result from associating members of low status groups with unfair circumstances. Because automatic associations predict prejudiced behaviors, the burden of proof is on those wishing to argue that egalitarian negative associations complicate the assessment of automatic attitudes rather than contribute to prejudiced responses. Discussion focuses on the implications of egalitarian negative associations for the theory and measurement of automatic prejudice.     

Can CBT Be Effective for Aboriginal Australians? Perspectives of Aboriginal Practitioners Trained in CBT

The objective of the study was to investigate whether high and low intensity versions of cognitive behaviour therapy (CBT) might be an effective therapeutic approach for enhancing the mental health of Aboriginal Australians. Five university‐educated Aboriginal counsellors received in‐depth training in CBT. Over the following year, they used CBT strategies with their clients, and met 10 times as a participatory action research group. The group addressed three key questions: (a) Does CBT appear to be useful for Aboriginal Australians? (b) If so, what elements of CBT are perceived to be effective? (c) What adaptations might be made to CBT to enhance its effectiveness with Aboriginal Australians? The resulting qualitative data were transcribed and analysed. Counsellors perceived CBT to be very useful for their Aboriginal clients and for themselves. They reported that it enhanced their clients' well‐being, their own clinical skills, and their own well‐being, and it reduced burnout. The qualities of CBT that were perceived to be effective were its adaptability, pragmatic here‐and‐now approach, capacity for low‐intensity interventions, safe containing structure, promotion of self‐agency, and valuable techniques. It was suggested that the prime requirement for adaptations to CBT were that they would need to fit different social and cultural contexts.     

The Product of Self-Deception

I raise the question of what cognitive attitude self-deception brings about. That is: what is the product of self-deception? Robert Audi and Georges Rey have argued that self-deception does not bring about belief in the usual sense, but rather “avowal” or “avowed belief.” That means a tendency to affirm verbally (both privately and publicly) that lacks normal belief-like connections to non-verbal actions. I contest their view by discussing cases in which the product of self-deception is implicated in action in a way that exemplifies the motivational role of belief. Furthermore, by applying independent criteria of what it is for a mental state to be a belief, I defend the more intuitive view that being self-deceived that p entails believing that p. Beliefs (i) are the default for action relative to other cognitive attitudes (such as imagining and hypothesis) and (ii) have cognitive governance over the other cognitive attitudes. I explicate these two relations and argue that they obtain for the product of self-deception.

Why do people with an anxiety disorder utilize more nonmental health care than those without?

OBJECTIVE: It is unclear why nonmental healthcare utilization is greater among those with psychological problems. The authors examined healthcare utilization in HMO patients to determine whether greater utilization in anxiety disorder (AD) patients was explained by anxiety symptoms (increasing sensitivity to physical symptoms) or comorbid illness (causing greater need for services). DESIGN: Patients were randomly selected from the database of a multi-specialty practice and 1,041 completed a survey assessing psychological symptoms, health behaviors, and demographics. Anxiety symptoms were assessed by questionnaire and the presence of an AD was determined from the medical chart. Healthcare encounters and medication use were abstracted from medical charts and HMO claims data. MAIN OUTCOME MEASURES: Healthcare utilization. RESULTS: Both AD and anxiety symptoms predicted utilization, but symptoms were not associated with utilization in a model that also included AD. Comorbid illness was significantly associated with utilization independent of AD and somewhat reduced the strength of the AD-utilization association. The results were replicated in comparison of those with any psychiatric disorder to those without. CONCLUSION: Among those with AD, greater utilization is not explained by anxiety symptoms but is partly explained by greater comorbid illness. Further study is needed to understand excess healthcare utilization among AD patients.     

Overcoming adolescents' resistance to anti-inhalant appeals.

This research was concerned with factors that affect adolescents' evaluations of persuasive anti-inhalant messages and the association of these evaluations with usage intentions. Sixth and 7th graders (N=894) received anti-inhalant messages that varied as a result of the factorial combination of message source (doctor or peer), suggested harm (social or physical), and target (message was addressed directly or indirectly to receivers). Manipulated variables were crossed with inhalant-user status (resolute nonuser, vulnerable nonuser, and user). Significant (p<.01) target and status effects on message evaluation were found. Significant interactions of status with each of the manipulated variables also emerged. Users were resistant to threatened physical harms, but suggested harms did not differentially affect resolute nonusers or vulnerable nonusers. Users and vulnerable nonusers evaluated the message more positively when targeted indirectly (p<.05). Vulnerable nonusers were more receptive to peer sources, whereas users preferred adult sources. Message evaluation was significantly associated with inhalant usage intentions (r=-.22), and this association held even after the contributions of sex, sensation seeking, acculturation, prior use, familism, and assumed peer usage were accounted for in a multiple regression analysis (overall R(2)=.24).     

Anxiety sensitivity within the anxiety disorders: disorder-specific sensitivities and depression comorbidity

The tendency to perceive anxious states as aversive and harmful is hypothesized to confer vulnerability to the development of anxiety disorders. The most commonly used measure of anxiety sensitivity, the Anxiety Sensitivity Index [ASI; Reiss, S., Peterson, R.A., Gursky, D.M., & McNally R.J. (1986). Anxiety sensitivity, anxiety frequency, and the prediction of fearfulness. Behavior Research and Therapy, 24, 1-8], is composed of multiple lower-order factors, assessing fear of physical symptoms, fear of publicly observable anxious symptoms, and fear of cognitive dyscontrol. This study examined the convergent validity of the lower-order anxiety sensitivity dimensions in DSM-IV diagnosed anxiety disorders. Participants with primary diagnoses of panic disorder with agoraphobia, social phobia, and generalized anxiety disorder (GAD) completed the ASI and measures of anxiety and depression severity. Support was found for the convergent validity of all ASI dimensions in reference to thematically related anxiety disorders and in the identification of patients presenting with and without secondary major depressive disorder (MDD). The ASI-fear of cognitive dyscontrol dimension displayed strong and nonredundant associations with GAD, dimensional depression scores, and secondary diagnoses of MDD. The conceptual implications of the shared importance of fear of cognitive dyscontrol in GAD and MDD are discussed.