Kernel methods for detecting coherent structures in dynamical data

We illustrate relationships between classical kernel-based dimensionality reduction techniques and eigendecompositions of empirical estimates of reproducing kernel Hilbert space (RKHS) operators associated with dynamical systems. In particular, we show that kernel canonical correlation analysis (CCA) can be interpreted in terms of kernel transfer operators and that it can be obtained by optimizing the variational approach for Markov processes (VAMP) score. As a result, we show that coherent sets of particle trajectories can be computed by kernel CCA. We demonstrate the efficiency of this approach with several examples, namely the well-known Bickley jet, ocean drifter data, and a molecular dynamics problem with a time-dependent potential. Finally, we propose a straightforward generalization of dynamic mode decomposition (DMD) called coherent mode decomposition (CMD). Our results provide a generic machine learning approach to the computation of coherent sets with an objective score that can be used for cross-validation and the comparison of different methods

El sistema de innovación design_driven como modelo estratégico y la propuesta de política nacional de diseño para Chile 2007

Durante el primer semestre de 2007 la autora en su calidad de Coordinadora Ejecutiva de la Comisión participó en la creación de una Propuesta de Política Nacional de Diseño para Chile. La propuesta fue presentada al Ministro de Economía de la época Sr. Alejandro Ferreiro, el 27 de julio del mismo año, en el evento MIPYME DISEÑA bajo el lema “Innovar, Crecer, Competir”. Esta propuesta de política pública se articuló teniendo como base conceptual y metodológica el Sistema de Innovación Design_driven (SID_d), modelo estratégico e instrumental que permite mapear y articular los habilitantes de una política de Innovación Design_driven. El SID_d está constituido por los actores, las actuaciones, los proyectos, la dimensión espacio-temporal, el modelamiento de procesos de Innovación Design_driven genera un sistema clasificatorio que permite caracterizar –al menos– tres tipologías: 1) SID_d nivel avanzado, 2) SID_d nivel intermedio y 3) SID_d nivel emergente. Por otra parte, este modelo como instrumento estratégico permite visualizar un modelo ideal para países en vías de desarrollo y es útil como referente para la propuesta de estrategias que fortalezcan el desarrollo, proyección y consolidación del Diseño en SID_d del tipo emergente. Este modelo fue desarrollado por la autora como resultado de su trabajo de tesis doctoral entre los años 2004 y 2006 y considera los resultados de la investigación realizada sobre cuatro casos europeos, España, Portugal, Italia y Finlandia, en los cuales el Diseño es parte del Sistema Nacional de Innovación. Este artículo explica la configuración del Sistema de Innovación Design_Driven (SID_d) como modelo estratégico base para el desarrollo del Diseño en países emergentes y revisa los principales componentes de la citada propuesta de Política Nacional de Diseño

The "claim to difference" versus the "claim to universalism" - a marginalia on aesthetic education

Der Beitrag gibt eine Antwort auf die Kritik von S. Hellekamps und H. U. Musolff in Heft 2/1993. In der Replik wird vor allem die Frage erörtert, ob moralische und ästhetische Erfahrungen/Diskurse in Kontinuität oder in Differenz zueinander stehen, besonders angesichts der Intersubjektivität, die auch für ästhetische Erfahrungen und Urteile geltend gemacht werden kann. Bereits die Beschreibung der Problemlage bereitet allerdings Schwierigkeiten. Sie lassen sich sowohl in den konventionellen Komponenten ästhetischer Bildung wie in ihrer Einbindung in kulturelle Formationen und schulische Curricula, als auch in ihrer Subjektkomponente finden. Es wird vermutet, daß unsere Vokabularien uns derzeit eine "dichte" Erörterung derartiger Fragen erschweren. (DIPF/Text übernommen)The article is written in answer to the critique by S, Hellekamps and H. U. Musolff, published in issue 2/1993. The author discusses above all the question whether the relation between moral and aesthetic experiences/discourses is one of continuity or of difference, especially in view of the intersubjectivity which can also be claimed for aesthetic experiences and judgements. The description of the problem itself already leads to difficulties, some of which are due to the conventional components of aesthetic education and to its integration into school curricula. It seems that, at present, our vocabularies impede a "dense" discussion of such questions. (DIPF/Orig.

On the Statistical Approximation of Conditional Expectation Operators

Diese Dissertation erörtert die datengetriebene Approximation des sogenannten conditional expectation operators, welcher den Erwartungswert einer reellwertigen Transformation einer Zufallsvariablen bedingt auf eine zweite Zufallsvariable beschreibt. Sie stellt dieses klassische numerische Problem in einem neuen theoretischen Zusammenhang dar und beleuchtet es mit verschiedenen ausgewählten Methoden der modernen statistischen Lerntheorie. Es werden sowohl ein bekannter parametrischer Projektionsansatz aus dem numerischen Bereich als auch ein nichtparametrisches Modell auf Basis eines reproducing kernel Hilbert space untersucht. Die Untersuchungen dieser Arbeit werden motiviert duch den speziellen Fall, in dem der conditional expectation operator die Übergangswahrscheinlichkeiten eines Markovprozesses beschreibt. In diesem Kontext sind die Spektraleigenschaften des resultierenden Markov transition operators von großem praktischen Interesse zur datenbasierten Untersuchung von komplexer Dynamik. Die oben genannten vorgestellten Schätzer werden in diesem Szenario in der Praxis verwendet. Es werden diverse neue Konvergenz- und Approximationsresultate sowohl für stochastisch unabhängige als auch abhängige Daten gezeigt. Als Werkzeuge für diese Ergebnisse dienen Konzepte aus den Theorien inverser Probleme, schwach abhängiger stochastischer Prozesse, der St ̈orung von Spektraleigenschaften und der Konzentration von Wahrscheinlichkeitsmaßen. Zur theoretischen Rechtfertigung des nichtparametrischen Modells wird das Schätzen von kernel autocovariance operators von stationären Zeitreihen untersucht. Diese Betrachtung kann zusätzlich vielfältig in anderen Zusammenhängen genutzt werden, was anhand von neuen Ergebnissen zur Konsistenz von kernelbasierter Hauptkomponentenanalyse mit schwach abhängigen Daten demonstriert wird. Diese Dissertation ist theoretischer Natur und dient nicht zur unmittelbaren Umsetzung von neuen numerischen Methoden. Sie stellt jedoch den direkten Zusammenhang von bekannten Ansätzen in diesem Feld zu relevanten statistischen Arbeiten der letzten Jahre her, welche sowohl stärkere theoretische Ergebnisse als auch effizientere praktische Schätzer für dieses Problem in der Zukunft möglich machen.This dissertation discusses the data-driven approximation of the so-called conditional expectation operator, which describes the expected value of a real-valued transformation of a random variable conditioned on a second random variable. It presents this classical numerical problem in a new theoretical context and examines it using various selected methods from modern statistical learning theory. Both a well-known parametric projection approach from the numerical domain and a nonparametric model based on a reproducing kernel Hilbert space are investigated. The investigations of this work are motivated by the special case in which the conditional expectation operator describes the transition probabilities of a Markov process. In this context, the spectral properties of the resulting Markov transition operator are of great practical interest for the data-based study of complex dynamics. The presented estimators are used in practice in this scenario. Various new convergence and approximation results are shown for both stochastically independent and dependent data. Concepts from the theories of inverse problems, weakly dependent stochastic processes, spectral perturbation, and concentration of measure serve as tools for these results. For the theoretical justification of the nonparametric model, the estimation of kernel autocovariance operators of stationary time series is investigated. This consideration can additionally be used in a variety of ways in other contexts, which is demonstrated in terms of new results on the consistency of kernel-based principal component analysis with weakly dependent data. This dissertation is theoretical in nature and does not serve to directly implement new numerical methods. It does, however, provide a direct link from known approaches in this field to relevant statistical work from recent years, which will make both stronger theoretical results and more efficient practical estimators for this problem possible in the future

Fifty Years of Remembering: Blato’s Kumpanjija in Sydney, Australia

The kumpanjija, or chain sword dance, of Blato, Croatia, is also danced each April in Sydney, Australia. This paper explores the perpetuation of the kumpanjija in Sydney since 1965, culminating in the fiftieth anniversary performance in 2015. Based on data from ethnographic fieldwork, the paper provides an ethnochoreological analysis of this event and illustrates how the performance fosters experiences of bonding, embodies nostalgic sentiment and provides community focus. The relationship between the dance as performed currently in Blato, and the performance troupe in Sydney is also explored. This event demonstrates the significance of the annual event for this section of the Croatian immigrant community in Sydney

Analytical performance and clinical utility of the INNOTEST (R) PHOSPHO-TAU(181P) assay for discrimination between Alzheimer's disease and dementia with Lewy bodies

Background: Total tau (T-tau) and beta-amyloid((1-42)) (A beta(1-42)) levels in cerebrospinal fluid (CSF) can differentiate Alzheimer's disease (AD) from normal aging or depressive pseudo-dementia. Differential diagnosis from dementia with Lewy bodies (DLB) in clinical settings is difficult. Methods: The analytical performance of the INNOTEST (R) PHOSPHO-TAU((181P)) assay was validated in terms of selectivity, sensitivity, specificity, precision, robustness, and stability. Clinical utility of the assay alone, or combined with T-tau and AP1-421 for discrimination of AD (n=94) from patients suffering from DLB (n=60) or from age-matched control subjects (CS) (n=60) was assessed in a multicenter study. Results: CSF concentrations of tau phosphorylated at threonine 181 (P-tau(181P)) in AD was significantly higher than in DLB and CS. Discriminant analysis, a classification tree, and logistic regression showed that P-tau(181P) was the most statistically significant single variable of the three biomarkers for discrimination between AD and DLB. Conclusions: P-tau(181P) quantification is a robust and reliable assay that may be useful in discriminating AD from DLB

Translated traditions: A comparative ethnography of traditional dance in the Irish and Croatian communities in Sydney, Australia

This comparative ethnography investigates the traditional dance practices of the Irish and Croatian communities in Sydney, Australia. Transnationalism theory affords the means through which to examine the multiple ways in which individuals and groups have forged, and continue to participate in, fields of engagement across national borders. The study situates the immigrant groups within the context of multicultural Australia, and additionally references the theoretical paradigms of cultural identity, diaspora studies, nostalgia theory and ethnochoreology. The research entailed detailed case studies of three dance groups from each of the immigrant communities under investigation. Data were gathered through ethnographic fieldwork conducted in dance classes and special events over two years and interviews with 100 participants. Emergent themes revealed participants’ agency in multiple transnational spaces including, at a personal level, cultural identity, emotional attachment and embodied signification. Themes relating to structural and functional fields were the global organisational frameworks, patterns of pedagogical practice and flows of material goods. The final theme was transnational representation through public performances of dance. The research revealed that participation in traditional dance was an important means through which immigrants may perpetuate links with their ancestral birthplace. Strong affective bonds with that former homeland were noted amongst the large majority of respondents. Dance was also identified as an important signifier of cultural belonging amongst members of both communities. Additionally, the study acknowledged that transnational engagements were not the sole province of immigrants, but also included those who have merely affiliated themselves with a traditional dance genre