Critical values improvement for the standard normal homogeneity test by combining Monte Carlo and regression approaches

The distribution of the test statistics of homogeneity tests is often unknown, requiring the estimation of the critical values through Monte Carlo (MC) simulations. The computation of the critical values at low α, especially when the distribution of the statistics changes with the series length (sample cardinality), requires a considerable number of simulations to achieve a reasonable precision of the estimates (i.e. 10⁶ simulations or more for each series length). If, in addition, the test requires a noteworthy computational effort, the estimation of the critical values may need unacceptably long runtimes.

To overcome the problem, the paper proposes a regression-based refinement of an initial MC estimate of the critical values, also allowing an approximation of the achieved improvement. Moreover, the paper presents an application of the method to two tests: SNHT (standard normal homogeneity test, widely used in climatology), and SNH2T (a version of SNHT showing a squared numerical complexity). For both, the paper reports the critical values for α ranging between 0.1 and 0.0001 (useful for the p-value estimation), and the series length ranging from 10 (widely adopted size in climatological change-point detection literature) to 70,000 elements (nearly the length of a daily data time series 200 years long), estimated with coefficients of variation within 0.22%. For SNHT, a comparison of our results with approximated, theoretically derived, critical values is also performed; we suggest adopting those values for the series exceeding 70,000 elements.     

On metaphors,everyday diversity and intercultural education: some further reflections

This paper aims to clarify and discuss the reasons and limits of three rather popular metaphors that are used to speak of today’s complex social and cultural fabric, through references to cultural anthropology, biology and genetics. In her analysis, the author considers not only the linguistic and semantic dimension of each metaphor, but also the pragmatic consequences each entails for the field of intercultural education. In her conclusion, she points out that exploring the many facets of metaphors is a form of intercultural education as it helps to deconstruct some of the current prejudices and stereotypes, and furthermore it encourages a disposition to creativity and intellectual openness that intrinsically belongs to the interculture.     

The Intermodal Bike: multi-modal integration of cycling mobility through product and process innovations in bicycle design

The paper presents the early results of the UE-FP7 project "The Intermodal Bike". The research aim is to provide a super-compactable, super-lightweight folding bicycle as a realistic solution to graft the cycling mode onto the root of the public or private transportation systems. The folding bikes now on the international market reach weighs between 12-15 kg, with a variable footprint but occupying -when compacted- an average volume of about 100 liters. To encourage the use of this vehicle and to extend it to a larger number of users with different characteristics, the research project has set its goal in increasing as possible compactness and light weight, creating a bicycle with a volume when compacted of 20 liters (reduction factor =5), with a shape of 48 × 36 × 12 cm and a weight of 5 kg. max., ensuring stability and improving vehicle usability and efficiency, during the ride and in the phase of bike folding. To achieve this goal ergonomic and usability tests have been carried out. The tests allowed to find a posture that would ensure efficiency and comfort in the ride to as many users as possible. Parallel tests were made on the vehicle usability in the urban transport system and intermodal. The need for light weight has required special studies on the optimization of the vehicle's architecture and research on super-lightweight materials.     

Experimenting new design languages in contemporary home design

The changes in society at the beginning of this millennium are giving rise to deep transformations in the behavioural trends and tastes of home users, as well as in their lifestyles and consumption patterns. This opens up a wide range of opportunities for innovation within the context of contemporary home design. Due to the emergence of new user profiles, new needs and models are coming to the attention of designers and manufacturing companies. Just think about the new needs resulting from the changing composition of households, new forms of cohabitation and the contemporary multi-ethnic society.     

Relational collaboration among spatial multipoint competitors

The presence of network ties between multipoint competitors is frequently assumed but rarely examined directly. The outcomes of multipoint competition, therefore, are better understood than their underlying relational mechanisms. Using original fieldwork and data that we have collected on an interorganizational network of patient transfer relations within a regional community of hospitals, we report and interpret estimates of Exponential Random Graph Models (ERGM) that specify the probability of observing network ties between organizations as a function of the degree of their spatial multipoint contact. We find that hospitals competing more intensely for patients across multiple geographical segments of their market (spatial multipoint competitors) are significantly more likely to collaborate. This conclusion is robust to alternative explanations for the formation of network ties based on organizational size differences, resource complementarities, performance differentials, and capacity constraints. We show that interorganizational networks between spatial multipoint competitors are characterized by clear tendencies toward clustering and a global core-periphery structure arising as consequences of multiple mechanisms of triadic closure operating simultaneously. We conclude that the effects of competition on the structure of interorganizational fields depends on how markets as physical and social settings are connected by cross-cutting network ties between competitors.     

The ‘proper’ way to spread ideas through social media: exploring the affordances and constraints of different social media platforms as perceived by Italian activists

Social media have become a relevant arena for different forms of civic engagement and activism. This article focuses on the affordances and constraints of different social media platforms as they are perceived by Italian activists. Instead of focusing on single protest movements, or on single platforms, we adopt a media ecological approach and consider a variety of environments where people can choose to express protest‐related content. Our main goal is to explore whether, and how, the affordances and constraints of different social media platforms are perceived by users, and how such perceived differences are integrated in everyday social media activities. To this end, we combined in‐depth interviews with an adapted version of the cognitive walkthrough and thinking aloud techniques. Respondents reported that they act on social media platforms according to specific representations of what each platform ‘is’, and how it works. Such perceptions affect users’ protest‐related social media practices. Although they perceive major social media platforms filtering strategies and are aware, to different extents, of their commodified nature, they report continuing to use them for activism‐related communication, often adopting an instrumental approach.     

The hydropolitical challenges of domestic water conservation. Palestine and Tunisia case studies

Southern Mediterranean area, particularly the Middle East and North Africa (MENA), has been facing social, economic, environmental and political challenges related to the water scarcity and quality. Within the European SWMED project, a socio-economic survey was conducted in Palestine and Tunisia, in order to explore the water conditions, and the social and economic situations of local families. The article illustrates the research design and implementation, as well as the main results that were used to select the appropriate sustainable water management solutions to respond to the hydropolitical issues. Due to the huge use of water in agriculture and the difficulty of reducing the water consumption in this sector, fostering tools for domestic water saving may be a winning strategy for facing water scarcity in MENA region.     

Voices of Nigerian Women Survivors of Trafficking Held in Italian Centres for Identification and Expulsion

This article examines the vicissitudes that affect the migration trajectories of many Nigerian women who experienced trafficking before arriving in Italy, and end up in Centers for Identification and Expulsion (CIE) for undocumented migrants. Their life stories, collected within the CIE of Ponte Galeria (Rome), revealed violence as “a rule of action” with which these women are obliged to cope with at different levels. Moreover, they highlighted the failure of traditional security approaches to human trafficking, and the necessity to rethink the measures adopted to ensure survivors' protection and rights. As it is conceived, the system of immigration control prevents the full guarantee of survivors' rights, often labelling them as “illegal migrants”. Finally, there is the need to extend protection to all survivors of human trafficking even if the crime against them has not happened in Italy.     

Marginal Players? The Third Sector and Employability Services for Migrants,Refugees and Asylum Seekers in the UK

VOLUNTAS: International Journal of Voluntary and Nonprofit Organizations - Literature in the field of employability and the third sector has focused upon the impact of marketisation on third sector...