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Understanding how players solve puzzles
No full textPen-and-paper puzzles offer a controlled environment to study problem-solving, player behaviour, and engagement. This abstract describes how players interact with unfamiliar puzzles, building upon existing research in the puzzle solving, explanation and hint-systems. We investigated how hints help players in explaining and/or indicating next steps in solving puzzles for a particular puzzle (Binairo). The analysis found that players using hints generally performed better, completed more puzzles, and showed signs of strategic thinking. This suggests that the availability of hints may have implications for playability, engagement and facilitating mental focus
On synthetic interval data with predetermined subject partitioning and partial control of the variables’ marginal correlation structure
No full textA standard approach for assessing the performance of partition models is to create synthetic datasets with a prespecified clustering structure and assess how well the model reveals this structure. A common format involves subjects being assigned to different clusters, with observations simulated so that subjects within the same cluster have similar profiles, allowing for some variability. In this manuscript, we consider observations from interval variables. Interval data are commonly observed in cohort and Genome-Wide Association studies, and our focus is on Single-Nucleotide Polymorphisms. Theoretical and empirical results are utilized to explore the dependence structure between the variables in relation to the clustering structure for the subjects. A novel algorithm is proposed that allows control over the marginal stratified correlation structure of the variables, specifying exact correlation values within groups of variables. Practical examples are shown, and a synthetic dataset is compared to a real one, to demonstrate similarities and differences
Do it like a tax haven:deny 24,000 children an education to send 2 to school
No full textBlog of research 'Profit shifting from Nigeria to Europe: the impact on human rights' (PLOS Global Health, 2025). Blog was republished by MSN news
Adam Watson and international relations: a contemporary reassessment - introduction
No full textThis is the introduction to the special issue 'Adam Watson and International Relations: A Contemporary Reassessment'. In this short piece, the guest editors outline the genesis, development, and purpose of the project, offer a rationale for the special issue, summarise the papers in it, and reflect on the importance of Adam Watson within the English School and International Relations canons
JA-TN: pick-and-place towel shaping from crumpled states based on TransporterNet with joint-probability action inference
No full textTowel manipulation is a crucial step towards more general cloth manipulation. However, folding a towel from an arbitrarily crumpled state and recovering from a failed folding step remain critical challenges in robotics. We propose joint-probability action inference JA-TN, as a way to improve TransporterNet’s operational efficiency; to our knowledge, this is the first single data-driven policy to achieve various types of folding from most crumpled states. We present three benchmark domains with a set of shaping tasks and the corresponding oracle policies to facilitate the further development of the field. We also present a simulation-to-reality transfer procedure for vision-based deep learning controllers by processing and augmenting RGB and/or depth images. We also demonstrate JA-TN’s ability to integrate with a real camera and a UR3e robot arm, showcasing the method’s applicability to real-world tasks
Bratman on institutional agency
No full textIn his recent book, Shared and Institutional Agency, Bratman attempts to defend realism about institutional agency while appealing only to ontologically modest foundations. Here I argue that this ontologically modest foundation leaves Bratman unable to provide plausible accounts of institutional evidence, institutional belief, and the reasons for which institutions believe and act. Given that these phenomena are key to our moral and epistemic evaluation of institutions and their actions, this is a serious failing. Instead, we should defend a more robust realism about institutional agency
A reinvestigation of cognitive styles in sticklebacks:decision success varies with behavioral type
No full textThe “cognitive styles” hypothesis suggests that individual differences in behavior are associated with variation in cognitive performance via underlying speed-accuracy trade-offs. While this is supported, in part, by a growing body of evidence, some studies did not find the expected relationships between behavioral type and cognitive performance. In some cases, this may reflect methodological limitations rather than the absence of a true relationship. The physical design of the testing arena and the number of choices offered in an assay can hinder our ability to detect inter-individual differences in cognitive performance. Here, we re-investigated the cognitive styles hypothesis in threespine stickleback (Gasterosteus aculeatus), adapting the maze design of a previous study which found no cost to decision success by faster (bolder) individuals. We used a similar design but increased the size of the maze and incorporated an additional choice in the form of a third maze arm. We found, in accordance with cognitive style expectations, that individuals who were consistently slower to emerge from the start chamber made fewer errors than fish that emerged faster. Activity in an open field test, however, did not show evidence of a relationship with decision success, possibly due to the low number of repeated observations per fish in this separate assay. Our results provide further empirical support for the cognitive styles hypothesis and highlight important methodological aspects to consider in studies of inter-individual differences in cognition
A history of studies of reproductive isolation between <i>Drosophila pseudoobscura</i> and <i>D. persimilis</i>
No full textDrosophila pseudoobscura and D. persimilis are a sister species pair that have been used as a model for studies of reproductive isolation and speciation for almost 100 years owing to their close evolutionary history, well characterized genetic differences, and overlapping geographic distribution. There are extensive analyses of both pre- and post-zygotic isolation, including studies of courtship divergence, conspecific sperm precedence (CSP) and how reinforcement by natural selection may or may not act to strengthen isolation in sympatry. Post-zygotic analyses explore the underlying mechanics of reproductive isolation; how inversions may give rise to initial speciation events and misexpression of key genes typically found within inversion regions render hybrid offspring unfit or inviable. We aim here to present a history of studies of reproductive isolation between this species pair, looking at how the field has developed over the last century and identifying the open questions and gaps within the literature
Kin competition drives the evolution of earlier metamorphosis
No full textMetamorphosis, the discrete morphological change between postembryonic life stages, is widespread across the animal kingdom. The suggested advantages of metamorphosis have usually been framed in terms of population benefits, i.e., ecological explanations. In contrast, evolutionary explanations concern whether and how metamorphosis spreads through a population owing to individual-fitness benefits. However, how kin selection modulates evolution of metamorphosis remains to be investigated formally. Here we develop a mathematical model to investigate how kin selection shapes the optimal timing of metamorphosis from foraging, non-reproductive larva to reproductive adult, when larvae tend to cluster with their genetic relatives. We consider the full range of larval competition intensities—from no competition to full competition—and the full range of relatedness coefficients—from unrelated to clonality. We provide testable predictions as to how kin selection modulates the timing of metamorphosis, as well as a conceptual framework within which empirical observations may be understood
Hierarchical political power and the value of cash holdings
No full textThis study examines the relationship between hierarchical political power and the value of cash holdings. To model the power structure, we utilize the hierarchical civil service system in China to distinguish between the holders of high- and low-level political power. We establish that directors with high-level political power increase the market value of cash, whereas those with low-level political power have no impact. Such effects are more pronounced in non-state-owned firms, in regions where politicians are subject to higher political pressure and in firms experiencing stronger agency conflicts. Further analysis shows that directors with high-level political power can increase the value of cash holdings through improved investment efficiency. Among directors with high-level political power, shareholders benefit most from the presence of those ranked at the Bureau-Department level. Our study provides original evidence that political hierarchy holds significance for investors’ valuation of cash holdings and emphasizes the importance of the heterogeneous nature of boards’ political capital in determining corporate value