Il laboratorio teatrale come strumento di indagine antropologica. Note di campo a margine di una ricerca etnografica in Repubblica Dominicana

L’articolo riporta la rielaborazione di alcune note di campo stese tra dicembre 2006 e gennaio 2007 durante una breve ricerca etnografica finalizzata alla scrittura della mia tesi di laurea specialistica, discussa, a luglio 2007, presso l’Università degli Studi di Milano Bicocca. Nell’articolo descrivo un percorso di ricerca partecipata organizzato con ragazzi di diverse comunità povere di Santiago de Los Caballeros (Repubblica Dominicana), rivolto alla comprensione delle loro interpretazioni rispetto certe dimensioni sociali che interessavano il contesto nel quale vivevano. Il percorso si è servito di una metodologia laboratoriale di stampo pedagogico-teatrale, elaborata a partire da alcune considerazioni avanzate da Victor Turner nel suo testo del 1982 “Dal rito al teatro”. La specificità e la provocatorietà dell’esperienza descritta consiste nella sperimentazione, seppur embrionale, di uno strumento di ricerca alternativo o complementare all’intervista, che potrebbe forse contribuire allo sviluppo di una metodologia della ricerca qualitativa concentrata non esclusivamente sul linguaggio verbale

Banditismo giovanile e mercato della sicurezza in un barrio di Città del Guatemala

È opinione comune ritenere che con la firma degli accordi di pace e lo smantellamento degli apparati militari in Guatemala sia venuto meno il monopolio dello Stato nella gestione della sicurezza pubblica. Nuovi spazi economici all’interno del mercato della sicurezza si sarebbero allora aperti; spazi presto occupati anche da attori armati e illegali quali narcotraf-ficanti e bande giovanili. L’autore analizza a questo proposito il processo di formazione delle prime maras (gang) e la fondazione di alcune ronde notturne in uno slum di Città del Guatemala a partire dalla seconda metà degli anni Ottanta.Generalmente se sostiene que en Guatemala, con la firma de los acuerdos de paz y el desmantelamiento de los aparatos militares, el Estado perdió su monopolio en la gestión de la seguridad pública. Nuevos espacios económicos se abrieron en el mercado de la seguridad. Actores armados no estatales (narcotraficantes y pandillas por ejemplo) los ocuparon. El autor analiza el origen de las primeras maras y la fundación de algunas rondas nocturnas en un asentamiento de la Ciudad de Guatemala a partir de la segunda mitad de los Ochentas.It is commonly argued that in Guatemala, after the peace accords and the dismantling of the military apparatus, the state no longer has the monopoly in the management of public security. New economic opportunities within the security market opened up; opportunities that were soon grabbed by illegal armed actors such as drug dealers and juvenile gangs. The author analyzes the process that led – from the second half of the 1980s – to the birth of the first maras (juvenile gangs) and the creation of some civil night patrols in a slum of Guatemala City

Systemic risk assessment through high order clustering coefficient

In this article we propose a novel measure of systemic risk in the context of financial networks. To this aim, we provide a definition of systemic risk which is based on the structure, developed at different levels, of clustered neighbours around the nodes of the network. The proposed measure incorporates the generalized concept of clustering coefficient of order $l$ of a node $i$ introduced in Cerqueti et al. (2018). Its properties are also explored in terms of systemic risk assessment. Empirical experiments on the time-varying global banking network show the effectiveness of the presented systemic risk measure and provide insights on how systemic risk has changed over the last years, also in the light of the recent financial crisis and the subsequent more stringent regulation for globally systemically important banks.Comment: Submitte

Model of tunneling transistors based on graphene on SiC

Recent experiments shown that graphene epitaxially grown on Silicon Carbide (SiC) can exhibit a energy gap of 0.26 eV, making it a promising material for electronics. With an accurate model, we explore the design parameter space for a fully ballistic graphene-on-SiC Tunnel Field-Effect Transistors (TFETs), and assess the DC and high frequency figures of merit. The steep subthreshold behavior can enable I_{ON}/I_{OFF} ratios exceeding 10^4 even with a low supply voltage of 0.15 V, for devices with gatelength down to 30 nm. Intrinsic transistor delays smaller than 1 ps are obtained. These factors make the device an interesting candidate for low-power nanoelectronics beyond CMOS

Market Dynamics When Agents Anticipate Correlation Breakdown

The aim of this paper is to analyse the effect introduced in the dynamics of a financial market when agents anticipate the occurrence of a correlation breakdown. What emerges is that correlation breakdowns can act both as a consequence and as a triggering factor in the emergence of financial crises rational bubbles. We propose a market with two kinds of agents: speculators and rational investors. Rational agents use excess demand information to estimate the variance-covariance structure of assets returns, and their investment decisions are represented as a Markowitz optimal portfolio allocation. Speculators are uninformed agents and form their expectations by imitative behavior, depending on market excess demand. Several market equilibria result, depending on the prevalence of one of the two types of agents. Differing from previous results in the literature on the interaction between market dynamics and speculative behavior, rational agents can generate financial crises, even without the speculator contribution

The anatomy of houses: Materialities of being at home

This introductory essay proposes a reflection that discusses, reframes, and presents the thematic section hosted in this volume, that investigates houses at the intersection between recent trends in the anthropology of the house, the study of material culture, and the investigation of contemporary socio-cultural transformations. In the first paragraph, we contextualize the growing contemporary interest in houses. In the second, following Carsten, we sustain the idea that houses themselves should be placed at the heart of a research agenda, we present the approach proposed in this thematic section, we clarify what are houses and what distinguishes them in relation to homes and households and how, in the history of anthropology, these “objects” have been investigated. In the third paragraph, reviewing the main approaches to the theme, we delve into the notion of société à maisons elaborated by Lévi-Strauss. The fourth paragraph places the concreteness of houses back at the centre of the analysis, where normative and material forms are mediated, reproduced, and even contested or negotiated. In the last, we present the three articles hosted in this thematic section – and the afterword discussing them – that explore how houses and their materiality modify the world and deal with its transformations.Questo saggio introduttivo propone una riflessione che discute, contestualizza e presenta la sezione tematica ospitata in questo volume, che indaga le case all’intersezione tra le recenti tendenze dell’antropologia della casa, lo studio della cultura materiale e l’indagine delle trasformazioni socio-culturali contemporanee. Nel primo paragrafo, contestualizziamo il crescente interesse contemporaneo per le case. Nel secondo, seguendo Carsten, sosteniamo l’idea che le case stesse debbano essere poste al centro di un’agenda di ricerca, presentiamo l’approccio proposto in questa sezione tematica, chiariamo cosa si intenda con “house” e cosa la distingua dai concetti di “home” e “household” e come, nella storia dell’antropologia, questi “oggetti” siano stati indagati. Nel terzo paragrafo, passando in rassegna i principali approcci al tema, approfondiamo la nozione di société à maisons elaborata da Lévi-Strauss. Il quarto paragrafo rimette al centro dell’analisi la concretezza delle case, dove le forme normative e materiali sono mediate, riprodotte e persino contestate o negoziate. Nell’ultimo, presentiamo i tre articoli etnografici ospitati in questa sezione tematica – e la postfazione che li discute – che esplorano come le case e la loro materialità modificano il mondo e affrontano le sue trasformazioni

Community structure in the World Trade Network based on communicability distances

In this paper, we investigate the mesoscale structure of the World Trade Network. In this framework, a specific role is assumed by short and long-range interactions, and hence by the distance, between countries. Therefore, we identify clusters through a new procedure that exploits Estrada communicability distance and the vibrational communicability distance, which turn out to be particularly suitable for catching the inner structure of the economic network. The proposed methodology aims at finding the distance threshold that maximizes a specific modularity function defined for general metric spaces. Main advantages regard the computational efficiency of the procedure as well as the possibility to inspect intercluster and intracluster properties of the resulting communities. The numerical analysis highlights peculiar relationships between countries and provides a rich set of information that can hardly be achieved within alternative clustering approaches.Comment: 40 pages, 19 figure

Taxonomy of Cohesion Coefficients for Weighted and Directed Multilayer Networks

Clustering and closure coefficients are among the most widely applied indicators in the description of the topological structure of a network. Many distinct definitions have been proposed over time, particularly in the case of weighted networks, where the choice of the weight attributed to the triangles is a crucial aspect. In the present work, in the framework of weighted directed multilayer networks, we extend the classical clustering and closure coefficients through the introduction of the clumping coefficient, which generalizes them to incomplete triangles of any type. We then organize the class of these coefficients in a systematic taxonomy in the more general context of weighted directed multilayer networks. Such cohesion coefficients have also been adapted to the different scales that characterize a multilayer network, in order to grasp their structure from different perspectives. We also show how the tensor formalism allows incorporating the new definitions, as well as all those existing in the literature, in a single unified writing, in such a way that a suitable choice of the involved adjacency tensors allows obtaining each of them. Finally, through some applications to simulated networks, we show the effectiveness of the proposed coefficients in capturing different peculiarities of the network structure on different scales