The Stability Theory of Knowledge and Belief Revision: Comments on Rott

In this commentary on Rotts paper Stability, Strength and Sensitivity: Converting Belief into Knowledge, I discuss two problems of the stability theory of knowledge which are pointed out by Rott. I conclude that these problems offer no reason for rejecting the stability theory, but might be grounds for deviating from the standard AGM account of belief revision which Rott presupposes.     

The abbreviated multidimensional acculturation scale: empirical validation with two Latino/Latina samples

Two studies were conducted to develop and examine internal consistencies and validate the Abbreviated Multidimensional Acculturation Scale. Study 1 participants were 156 Latino/Latina college students. Findings indicated good internal reliabilities for all 3 subscales. Adequate concurrent validity was established with length of residence in the United States. The scale also showed adequate convergent and discriminant validity. Study 2 participants were 90 Latino/Latina community members. The subscales were also reliable and showed adequate concurrent validity with length of residence in the United States. Convergent and discriminant validity were also adequate. Construct validity was further demonstrated through factorial analyses of the combined samples (N = 246). Three separate factors emerged: cultural identity, language competence, and cultural competence.     

Influence of spatial environment on maze learning in an African mole-rat

In subterranean species where excavation is energetically expensive, efficient spatial navigation is vital to reducing the costs of locating important resources such as food and mates. While spatial navigational ability is positively correlated with sociality in subterranean mammals, we have a less clear understanding of the role of habitat complexity on navigational ability. We tested spatial navigational ability and memory in 12-18-month captive Natal mole-rats (Cryptomys hottentotus natalensis) maintained in a simple environment with no environmental enrichment and newly captured wild individuals from natural, complex burrow systems. In maze trials, mole-rats captured freshly from the wild made significantly fewer navigational errors, were more likely to successfully navigate the maze, travelled shorter distances and as a consequence, completed the maze in less time. Male mole-rats from both experimental treatments were more likely to complete the maze than females. Memory retention of the maze was tested on day two, seven, 30 and 60, respectively. The results were variable, although both groups showed a significant memory retention 60?days after testing. Our results highlight the potential importance of the environment (microhabitat complexity) on spatial cognitive performance in mole-rats.     

Experiment and theory building

I examine the role of inference from experiment in theory building. What are the options open to the scientific community when faced with an experimental result that appears to be in conflict with accepted theory? I distinguish, in Laudan’s (1977), Nickels’s (1981), and Franklin’s (1993) sense, between the context of pursuit and the context of justification of a scientific theory. Making this distinction allows for a productive middle position between epistemic realism and constructivism. The decision to pursue a new or a revised theory in response to the new evidence may not be fully rationally determined. Nonetheless, it is possible to distinguish the question of whether there is reason to pursue a theory from the question of whether that theory, once it has been pursued over time, solves a problem of interest to science. I argue that, in this context, there is a solid way to distinguish between the contexts of pursuit and of justification, on the basis of a theory’s evidential support and problem-solving ability.     

Social comparison mediates chimpanzees’ responses to loss,not frustration

Why do chimpanzees react when their partner gets a better deal than them? Do they note the inequity or do their responses reflect frustration in response to unattainable rewards? To tease apart inequity and contrast, we tested chimpanzees in a series of conditions that created loss through individual contrast, through inequity, or by both. Chimpanzees were tested in four social and two individual conditions in which they received food rewards in return for exchanging tokens with an experimenter. In conditions designed to create individual contrast, after completing an exchange, the chimpanzees were given a relatively less-preferred reward than the one they were previously shown. The chimpanzees’ willingness to accept the less-preferred rewards was independent of previously offered foods in both the social and individual conditions. In conditions that created frustration through inequity, subjects were given a less-preferred reward than the one received by their partner, but not in relation to the reward they were previously offered. In a social context, females were more likely to refuse to participate when they received a less-preferred reward than their partner (disadvantageous inequity), than when they received a more-preferred reward (advantageous inequity). Specifically, the females’ refusals were typified by refusals to exchange tokens rather than refusals to accept food rewards. Males showed no difference in their responses to inequity or individual contrast. These results support previous evidence that some chimpanzees’ responses to inequity are mediated more strongly by what others receive than by frustration effects.     

Job demands and psychological well-being: Moderating role of occupational self-efficacy and job social support among mid-career academics

The study investigated the moderating role of occupational self-efficacy and job social support on the relationship between job demands and psychological well-being among mid-career academics. Participants were 203 academics at three public Nigerian universities (female = 37.93%; mean years of service = 8.58 years, SD = 2.20). The academics completed measures of job demands, occupational self-efficacy, job social support, and psychological well-being. Moderated regression analysis of the data suggested only occupational self-efficacy to moderate the relationship between work demands and psychological well-being. Findings underpin the buffering effects of work self-efficacy in employee psychological well-being with high job demands.     

Comparative analysis of the risk-handling procedures for gene technology applications in medical and plant science

In this paper we analyse how the risks associated with research on transgenic plants are regulated in Sweden. The paper outlines the way in which pilot projects in the plant sciences are overseen in Sweden, and discusses the international and national background to the current regulatory system. The historical, and hitherto unexplored, reasons for the evolution of current administrative and legislative procedures in plant science are of particular interest. Specifically, we discuss similarities and differences in the regulation of medicine and plant science, and we examine the tendency towards dichotomizing risk — focusing on social/ethical risks in medicine and biological risks in plant science. The context of this article is the Synpraxia research project, an inter-disciplinary program combining expertise in sciences and the humanities.     

Examining the relationship between free recall and immediate serial recall: the effect of concurrent task performance

In 3 experiments, participants saw lists of 16 words for free recall with or without a 6-digit immediate serial recall (ISR) task after each word. Free recall was performed under standard visual silent and spoken-aloud conditions (Experiment 1), overt rehearsal conditions (Experiment 2), and fixed rehearsal conditions (Experiment 3). The authors found that in each experiment, there was no effect of ISR on the magnitude of the recency effect, but interleaved ISR disrupted free recall of those words that would otherwise be rehearsed. The authors conclude that ISR and recency cannot both be outputs from a unitary limited-capacity short-term memory store and discuss the possibility that the process of rehearsal may be common to both tasks.     

The ad coefficient as a descriptive measure of the within‐group agreement of ratings

The a_d coefficient was developed to measure the within‐group agreement of ratings. The underlying theory as well as the construction of the coefficient are explained. The a_d coefficient ranges from 0 to 1, regardless of the number of scale points, raters, or items. With some limitations the measure of the within‐group agreement of different groups and groups from different studies is directly comparable. For statistical significance testing, the binomial distribution is introduced as a model of the ratings' random distribution given the true score of a group construct. This method enables a decision about essential agreement and not only about a significant difference from 0 or a chosen critical value. The a_d coefficient identifies a single true score within a group. It is not provided for multiple true score settings. The comparison of the a_d coefficient with other agreement indices shows that the new coefficient is in line with their outcomes, but does not result in infinite or inappropriate values.