On Quantitative and Qualitative Parsimony

The distinction between quantitative and qualitative parsimony is supposed to allow David Lewis to dismiss one of the charges against his modal realism: that is, the charge of bloated ontology. The aim of this paper is to undermine Lewis's response to this objection. In order to do this, a distinction between multipliable and nonmultipliable objects is introduced. Based on this it is argued that the acceptance of Lewis's response requires one to believe in modal realism in the first place—that is, one has to believe in the view that the existence of nonactual spatiotemporal worlds does not affect the quality of the ontological commitment. Although the paper focuses on the problem of the metaphysics of possible worlds, this should be regarded merely as a case study. Accordingly, the results of this analysis should find applications in other metaphysical debates as well.     

The natural mathematics of behavior analysis

Models that generate event records have very general scope regarding the dimensions of the target behavior that we measure. From a set of predicted event records, we can generate predictions for any dependent variable that we could compute from the event records of our subjects. In this sense, models that generate event records permit us a freely multivariate analysis. To explore this proposition, we conducted a multivariate examination of Catania's Operant Reserve on single VI schedules in transition using a Markov Chain Monte Carlo scheme for Approximate Bayesian Computation. Although we found systematic deviations between our implementation of Catania's Operant Reserve and our observed data (e.g., mismatches in the shape of the interresponse time distributions), the general approach that we have demonstrated represents an avenue for modelling behavior that transcends the typical constraints of algebraic models.     

Detecting Clusters/Communities in Social Networks

Cohen's κ, a similarity measure for categorical data, has since been applied to problems in the data mining field such as cluster analysis and network link prediction. In this paper, a new application is examined: community detection in networks. A new algorithm is proposed that uses Cohen's κ as a similarity measure for each pair of nodes; subsequently, the κ values are then clustered to detect the communities. This paper defines and tests this method on a variety of simulated and real networks. The results are compared with those from eight other community detection algorithms. Results show this new algorithm is consistently among the top performers in classifying data points both on simulated and real networks. Additionally, this is one of the broadest comparative simulations for comparing community detection algorithms to date.     

An empirical investigation of a theoretical model for mathematical creativity

In this exploratory study, a theoretical model proposed by Sriraman (2005) consisting of five theoretical principles for optimizing creativity in a K–12 setting was investigated empirically. This was accomplished in two steps. In the first study, the five principles were operationalized by generating a questionnaire consisting of 45 items intended to capture the dimension of each principle. An exploratory maximum‐likelihood factor analysis indicated a relatively robust five factor structure that corresponded with the theoretical model. In the second study, the five factor model was validated using a confirmatory factor analysis. The model was then investigated using a two‐level linear mixed model with a random intercept. The results revealed that motivation and mathematical achievement were significant predictors of mathematical creativity.     

The Visual Spatial Learning Test: Differential impairment during the premanifest and manifest stages of Huntington's disease

Visual spatial memory was assessed using the Visual Spatial Learning Test (VSLT) in individuals with mild to moderate Huntington's disease (HD), pre‐manifest gene carriers for HD, and demographically similar controls. The VSLT has been demonstrated to be a valid, normed measure of non‐verbal memory involving minimal motoric responses. The VSLT assesses immediate and delayed memory for designs, positions of the designs, and design/position associations. The HD group was significantly impaired (p < .05) relative to both the control and Pre‐HD groups on immediate and delayed memory for the designs, positions, and design/position associations. Although there were no differences between the Pre‐HD and control groups on immediate or delayed memory for designs or positions, the Pre‐HD group was significantly impaired (p < .05) relative to the control group on immediate and delayed memory for design/position associations. The results offer novel insight into a relatively unexamined memory deficit that may occur in gene carriers for HD prior to phenoconversion. The data indicate that the VSLT may be a useful measure of visuospatial memory during the premanifest and manifest stages of HD.     

A Method for Universal Screening of Elementary School Students: Development of the Social Challenges Screening Questionnaire

Schools regularly screen students for hearing and vision impairments because they present impediments to academic progress. For the same reason, schools should consider adding a universal screening for social challenges, which may also impede the learning process. This study reports on the development of the Social Challenges Screening Questionnaire (SCSQ), an efficient teacher-report screening questionnaire that identifies students with challenges who may benefit from a psychological evaluation. Further, the questionnaire may help identify students with Autism Spectrum Disorder who were previously undiagnosed. The SCSQ was administered to 549 general education students in the third and fourth grades. Internal consistency was.85. A smaller sample of students (n = 50) was selected for additional follow up assessment using the Social Responsiveness Questionnaire, Second Edition. Scores on the two instruments were strongly correlated (r =.87, p <.01), and sensitivity (.94) and specificity (.88) indicate the SCSQ can efficiently detect students with social challenges in need of a formal evaluation.     

Embodiment Effects and Language Comprehension in Alzheimer's Disease

It has been shown that when participants are asked to make sensibility judgments on sentences that describe a transfer of an object toward or away from their body, they are faster to respond when the response requires a movement in the same direction as the transfer described in the sentence. This phenomenon is known as the action compatibility effect (ACE). This study investigates whether the ACE exists for volunteers with Alzheimer's disease (AD), whether the ACE can facilitate language comprehension, and also whether the ACE can still be produced if the order of the two events is inverted, that is, whether overt movement can prime comprehension of transfer sentences. In Study 1, participants with AD, younger, and older adults were tested on an adaptation of the ACE Paradigm. In Study 2, the same paradigm was modified to include an arm movement that participants had to perform prior to sentence exposure on screen. In Study 1, young, older adults, and individuals with AD were faster to respond when the direction of the response movement matched the directionality implied by the sentence (ACE). In Study 2, no traditional ACE was found; participants were faster when the direction of the movement immediately preceding the sentence matched the directionality of the sentence. It was found that compatibility effects generated a relative advantage, that transfer schemata are easier to process, and that an ACE‐like effect can be the result of mutual priming between language and movement. Results suggested preservation in AD of the neural systems for action engaged during language comprehension, and conditions under which comprehension in AD can be facilitated in real life may be identified.     

Making Probabilistic Relational Categories Learnable

Theories of relational concept acquisition (e.g., schema induction) based on structured intersection discovery predict that relational concepts with a probabilistic (i.e., family resemblance) structure ought to be extremely difficult to learn. We report four experiments testing this prediction by investigating conditions hypothesized to facilitate the learning of such categories. Experiment 1 showed that changing the task from a category‐learning task to choosing the “winning” object in each stimulus greatly facilitated participants' ability to learn probabilistic relational categories. Experiments 2 and 3 further investigated the mechanisms underlying this “who's winning” effect. Experiment 4 replicated and generalized the “who's winning” effect with more natural stimuli. Together, our findings suggest that people learn relational concepts by a process of intersection discovery akin to schema induction, and that any task that encourages people to discover a higher order relation that remains invariant over members of a category will facilitate the learning of putatively probabilistic relational concepts.     

Transmitting pro‐environmental behaviours to the next generation: A comparison between Germany and Japan

The present study examined the processes by which children acquire pro‐environmental behaviours in different cultures. Our focus was on parental influence. Several studies have been conducted on adults' environmental behaviours; however, we know little about how children's environmental attitudes and behaviours are formed. We conducted a questionnaire survey with elementary school children and one of their parents in Germany and Japan. Two hundred and twenty‐one pairs participated in Germany and 365 in Japan. The results of structural equation modelling showed that parents' behaviours affected children's environmental behaviours directly and also via the subjective norm (the children's experienced expectations of their parents). A comparison of the two countries revealed that hypothesized cultural differences between the impact of personal norms and subjective norms were clearer for adults. The results also showed that the effects of subjective norms were stronger for children, indicating that children are more likely to be influenced by expectations of others. The results of the study suggest that for promoting children's environmental behaviours, showing the behaviours in daily life would be most effective.