Nonparametric Bayesian grouping methods for spatial time-series data

We describe an approach for identifying groups of dynamically similar locations in spatial time-series data based on a simple Markov transition model. We give maximum-likelihood, empirical Bayes, and fully Bayesian formulations of the model, and describe exhaustive, greedy, and MCMC-based inference methods. The approach has been employed successfully in several studies to reveal meaningful relationships between environmental patterns and disease dynamics.Comment: 11 pages, no figure

Reflection factorizations of Singer cycles

Abstract. The number of shortest factorizations into reflections for a Singer cycle inGLn(Fq) is shown to be (q n − 1) n−1. Formulas counting factorizations of any length, and counting those with reflections of fixed conjugacy classes are also given. Résumé. Nous prouvons que le nombre de factorisations de longueur minimale d’un cycle de Singer dans GLn(Fq) comme un produit de réflexions est (q n −1) n−1. Nous présentons aussi des formules donnant le nombre de factorisations de toutes les longueurs ainsi que des formules pour le nombre de factorisations comme produit de réflexions ayant des classes de conjugaison fixes

Stakeholder Views on Interactions between Low-carbon Policies and Carbon Markets in China: Lessons from the Guangdong ETS

China set up pilot Emission Trading Schemes (ETS) in seven cities and provinces from 2013 as a new instrument to incentivise carbon dioxide emission reduction and to reach its 40-45% carbon intensity reduction target by 2020. Using a two-stage survey (a closed-form questionnaire followed by open interviews), we elicit views of stakeholders from Guangdong province on carbon markets, with an emphasis on how ETS would interact with other existing or proposed low-carbon and clean energy policies. Our survey shows that academic stakeholders viewed the interactions between the carbon market and other lowcarbon policies as a significant potential problem but there was less awareness by stakeholders from other sectors. There is a positive correlation between recognising such policy interactions may pose a problem and the time spent working on energy saving and emission reduction policies. Whereas both increasing renewable targets and imposing a carbon tax in addition to an existing ETS would be expected to depress prices in the ETS, relatively few respondents identified this effect correctly. Apart from government respondents, all other stakeholders lacked confidence in China's carbon markets, which is associated with both their lack of knowledge and information about the market and concerns regarding uncertainties and government policy design. The need for learning from the pilot schemes particularly on monitoring, reporting and verification was seen as vital but challenging given the speed of rolling out a national ETS

Updating our selves : synthesizing philosophical and neurobiological perspectives on incorporating new information into our worldview

Given the ubiquity and centrality of social and relational influences to the human experience, our conception of self-governance must adequately account for these external influences. The inclusion of socio-historical, externalist (i.e., “relational”) considerations into more traditional internalist (i.e., “individualist”) accounts of autonomy has been an important feature of the debate over personal autonomy in recent years. But the relevant socio-temporal dynamics of autonomy are not only historical in nature. There are also important, and under-examined, future-oriented questions about how we retain autonomy while incorporating new values into the existing set that guides our interaction with the world. In this paper, we examine these questions from two complementary perspectives: philosophy and neuroscience. After contextualizing the philosophical debate, we show the importance to theories of autonomous agency of the capacity to appropriately adapt our values and beliefs, in light of relevant experiences and evidence, to changing circumstances. We present a plausible philosophical account of this process, which we claim is generally applicable to theories about the nature of autonomy, both internalist and externalist alike. We then evaluate this account by providing a model for how the incorporation of values might occur in the brain; one that is inspired by recent theoretical and empirical advances in our understanding of the neural processes by which our beliefs are updated by new information. Finally, we synthesize these two perspectives and discuss how the neurobiology might inform the philosophical discussion

High transport currents in mechanically reinforced MgB2 wires

We prepared and characterized monofilamentary MgB2 wires with a mechanically reinforced composite sheath of Ta(Nb)/Cu/steel, which leads to dense filaments and correspondingly high transport currents up to Jc = 10^5 A/cm^2 at 4.2 K, self field. The reproducibility of the measured transport currents was excellent and not depending on the wire diameter. Using different precursors, commercial reacted powder or an unreacted Mg/B powder mixture, a strong influence on the pinning behaviour and the irreversibility field was observed. The critical transport current density showed a nearly linear temperature dependency for all wires being still 52 kA/cm^2 at 20 K and 23 kA/cm^2 at 30 K. Detailed data for Jc(B,T) and Tc(B) were measured.Comment: 21 pages, 13 figures, revised version, to be published in Supercond. Sci. Techno

Quaternion algebras with the same subfields

G. Prasad and A. Rapinchuk asked if two quaternion division F -algebras that have the same subfields are necessarily isomorphic. The answer is known to be "no" for some very large fields. We prove that the answer is "yes" if F is an extension of a global field K so that F /K is unirational and has zero unramified Brauer group. We also prove a similar result for Pfister forms and give an application to tractable fields

Historical Criminology and the Explanatory Power of the Past

To what extent can the past ‘explain’ the present? This deceptively simple question lies at the heart of historical criminology (research which incorporates historical primary sources while addressing present-day debates and practices in the criminal justice field). This article seeks first to categorise the ways in which criminologists have used historical data thus far, arguing that it is most commonly deployed to ‘problematize’ the contemporary rather than to ‘explain’ it. The article then interrogates the reticence of criminologists to attribute explicative power in relation to the present to historical data. Finally, it proposes the adoption of long time-frame historical research methods, outlining three advantages which would accrue from this: the identification and analysis of historical continuities; a more nuanced, shared understanding of micro/macro change over time in relation to criminal justice; and a method for identifying and analysing instances of historical recurrence, particularly in perceptions and discourses around crime and justice