Group disagreement: a belief aggregation perspective

The debate on the epistemology of disagreement has so far focused almost exclusively on cases of disagreement between individual persons. Yet, many social epistemologists agree that at least certain kinds of groups are equally capable of having beliefs that are open to epistemic evaluation. If so, we should expect a comprehensive epistemology of disagreement to accommodate cases of disagreement between group agents, such as juries, governments, companies, and the like. However, this raises a number of fundamental questions concerning what it means for groups to be epistemic peers and to disagree with each other. In this paper, we explore what group peer disagreement amounts to given that we think of group belief in terms of List and Pettit’s (Econ Philos 18:89–110, 2002; Group agency: the possibility, design, and status of corporate agents, Oxford University Press, Oxford, 2011) ‘belief aggregation model’. We then discuss how the so-called ‘equal weight view’ of peer disagreement is best accommodated within this framework. The account that seems most promising to us says, roughly, that the parties to a group peer disagreement should adopt the belief that results from applying the most suitable belief aggregation function for the combined group on all members of the combined group. To motivate this view, we test it against various intuitive cases, derive some of its notable implications, and discuss how it relates to the equal weight view of individual peer disagreement.

     

Precipitation of γ’ during cooling of nickel-base superalloy Haynes 282

ABSTRACT

Cooling-induced precipitation of the strengthening γ’ phase is commonly investigated in Ni-base superalloys with a high γ’ volume fraction, where it is used to control the final microstructure and properties. Less is known about the phase separation in low-volume-fraction alloys during cooling, although the microstructural state after cooling from solution treatment is known to affect subsequent heat-treatment steps. We use atomic-scale characterisation of Ni-base superalloy Haynes 282 (equilibrium γ’ volume fraction around 20%) to show that air cooling after solution or carbide stabilisation results in precipitation of nm-sized γ’ particles, whereas precipitation was suppressed during water quenching. The solution treatment has a significant effect on the hardness and γ’ precipitation during air cooling from the subsequent carbide stabilisation temperature. Also, the carbide-stabilisation treatment itself affects the γ’ precipitation during subsequent air cooling.     

Harnessing graphics processing units for improved neuroimaging statistics

Simple models and algorithms based on restrictive assumptions are often used in the field of neuroimaging for studies involving functional magnetic resonance imaging, voxel based morphometry, and diffusion tensor imaging. Nonparametric statistical methods or flexible Bayesian models can be applied rather easily to yield more trustworthy results. The spatial normalization step required for multisubject studies can also be improved by taking advantage of more robust algorithms for image registration. A common drawback of algorithms based on weaker assumptions, however, is the increase in computational complexity. In this short overview, we will therefore present some examples of how inexpensive PC graphics hardware, normally used for demanding computer games, can be used to enable practical use of more realistic models and accurate algorithms, such that the outcome of neuroimaging studies really can be trusted.     

An Expectancy-Value Approach to Determinants of Trust

An expectancy-value model was used to test determinants of trust in 5 Swedish organizations. Trust was conceptualized as an attitude, dependent on respondents' beliefs about and evaluations of the organization with respect to attributes of trustworthiness. A survey was sent out to a representative sample of the Swedish population ( N  = 347; response rate = 55.5%). It was found that the model was powerful in explaining trust in 3 of the 5 organizations. Values correlated more with observed trust in all organizations. It is discussed whether these findings could be explained by trust ratings based on ideologies. Since the expectancy-value approach was insufficient to account for data, a double-denial model ( Sjöberg & Montgomery, 1999 ) was needed.     

The factorial structure of the Dutch translation of the inventory of interpersonal problems: a test of the long and short versions

In this article, the authors study the factorial structure of 2 versions (64 items and 32 items) of the Dutch translation of the Inventory of Interpersonal Problems (IIP; L. M. Horowitz, L. E. Alden, J. S. Wiggins, & A. L. Pincus, 2000) in both a clinical sample (n = 382) and a student sample (n = 287). First, the authors test whether both inventories are constituted by correlated uni-dimensional subscales, and they conclude that this is true only for the short version. Second, the authors study whether the correlations between the subscales follow a circumplex pattern. This proves to be true for both versions. Coefficients alpha and correlations between the IIP-64 and IIP-32 subscales are discussed.     

A systematic program to enhance clinician group skills in an inpatient psychiatric hospital

This article describes the collaborative effort of a team of discipline directors, administrators, and academicians to create a systematic program to enhance the group competencies of a large clinical staff working at a state hospital. The effects of the program were tested by a quasi-experimental field study. Quantitative measures of group process provided limited support for program effectiveness. Stronger support came from qualitative inquiry. The development and effectiveness of the program is examined within a larger context of group programs housed in large health care organizations.     

Memory for pro-social intentions: When competing motives collide

Memory for future actions, or prospective memory (PM), often involves remembering to do things for others. The present article explores the motivational mechanisms underlying memory for pro-social intentions through the manipulation of the social relevance of goals and presence of material rewards during an activity-based PM task. Results revealed that memory for the intention was better under pro-social than under standard conditions. However, when a material reward was introduced under pro-social conditions, it had the detrimental effect of reducing prospective remembering. Ongoing task performance was faster under pro-social than under No PM and standard PM conditions and it was unrelated to PM performance. In addition, the outcome of the ratings of two independent groups of participants confirmed that people are not aware of the potential conflict between pro-social and self-gain motives. Taken together, these new findings extend current PM theories by suggesting a prominent role of latent motivational mechanisms in guiding memory for pro-social intentions.