Generating a smallest binary tree by proper selection of the longest edges to bisect in a unit simplex refinement

In several areas like global optimization using branch-and-bound methods for mixture design, the unit n-simplex is refined by longest edge bisection (LEB). This process provides a binary search tree. For \(n>2\), simplices appearing during the refinement process can have more than one longest edge (LE). The size of the resulting binary tree depends on the specific sequence of bisected longest edges. The questions are how to calculate the size of one of the smallest binary trees generated by LEB and how to find the corresponding sequence of LEs to bisect, which can be represented by a set of LE indices. Algorithms answering these questions are presented here. We focus on sets of LE indices that are repeated at a level of the binary tree. A set of LEs was presented in Aparicio et al. (Informatica 26(1):17–32, 2015), for \(n=3\). An additional question is whether this set is the best one under the so-called \(m_k\)-valid condition.     

‘Are you gonna show this to white people?’: Chicana/o and Latina/o students’ counter-narratives on race,place, and representation

This article explores the recurring narratives on race, place and representation that emerged in the talk of Chicana/o and Latina/o sixth-graders at a middle school in East Los Angeles, California. Discourse analytic methods are used to closely examine how these narratives were constructed within the contexts of everyday classroom interactions. Drawing on the notion of counter-storytelling from critical race theory, the article highlights how these sixth-grade students articulated counter-narratives about who they were and what their community was like – often in direct opposition to what they perceived as white people’s stereotypical assumptions and misperceptions. It is argued that these narratives constitute a powerful and sophisticated critique of dominant narratives that frame working-class Chicana/o and Latina/o students in racist and pejorative terms. The article ends with a discussion of implications for understanding youth agency and the politics of representation.     

Being a desirable migrant: perception and racialisation of Icelandic migrants in Norway

In the aftermath of the financial crisis that hit Iceland in October 2008, increased numbers of Icelanders migrated to Norway to seek employment due to difficult economic circumstances in Iceland. Using critical perspectives from postcolonial studies and critical whiteness studies, the paper explores how these Icelandic migrants in Norway make sense of their new position as economic migrants within a global economy characterised by a growing sense of precariousness, while past inequalities and racism continue to matter. We also examine how these migrants are perceived in Norwegian media, and how social discourses of Icelandic migrants reflect larger Norwegian debates on racism, desirability and cultural belonging. Media discourses in Norway and interviews with Icelandic migrants reveal a hierarchy of acceptability of migrants. Icelanders are positioned as highly desirable compared to other migrant groups due to the intersection of perceived racial belonging, nationality and class. Our discussion contributes, furthermore, towards a critical analysis of the category migrant, by exploring how the term immigrant (innvandrer/innflytjandi) is used in narratives of Icelandic migrants in Norway and in Norwegian media discussions, showing the negative and racialised connotations of the term immigrant and how its understanding is linked with vulnerable positions and discrimination.     

Open innovation and quality management: the moderating role of interorganisational IT infrastructure and complementary learning styles

This study seeks to explain the influence of quality management on the relationship between open innovation and performance. We propose that, to contribute to open innovation performance, an organisation’s commitment to quality improvement must rely on the combination of its own resources and capabilities and its open innovation partners’ resources and capabilities. Specifically, we examine the moderating role of an interorganisational IT infrastructure and the complementarity of learning styles among an organisation committed to quality improvement and its supply network. Using data from 270 managers of European firms, our results show that the negative effects of quality management on open innovation performance can be overcome by complementing the organisation’s learning style with that of its open innovation partner, particularly, its supply network, and, most importantly, obtaining information technologies compatible with those of its supply network members.     

Threatened plant species in the river ports of Central Europe: a potential for nature conservation

Industrialized areas represent a special group of urbanized areas, but sufficient attention has not been given to them concerning plant species richness and its importance for biodiversity conservation. These sites are considered the main drivers of biological invasions and biotic homogenization on a global scale, but the question of how and to what degree they contribute to biodiversity has yet to be raised. Data for 62 river ports (16 German, 26 Czech, 7 Hungarian, 4 Slovak, and 9 Austrian) on two important Central European waterways (the Elbe-Vltava and Danube waterways) were gathered for 40 years. In total, 1 240 plant species were found. Of these, 371 were classified as threatened and protected, nearly one third of the total number of species found in all of the studied Elbe, Vltava, and Danube ports. Significant differences in the proportion of threatened species in ports and cities were not found. More threatened species were found in the Danube ports than in the other ports, but their numbers fluctuated depending on the size of the port and the region (country). The results showed that the ports must be regarded as special types of species-rich industrial areas; thus, they should not be considered to be only sources of spreading invasive alien species. When planning port development, uniformity and vegetation management that is too intensive should be avoided. Extensively managed open areas and habitat diversity should be maintained.

     

Teachers’ Knowledge and Beliefs About Child Sexual Abuse

Child sexual abuse is one of the main types of abuse still to be addressed within the field of education, yet the education system itself can serve as a primary tool for its prevention. A better understanding of teachers’ knowledge and beliefs about child sexual abuse will allow us to establish key starting points from which to utilize the system for prevention. Four hundred and fifty teachers participated in this study, completing a questionnaire regarding their knowledge and beliefs about child sexual abuse. The study revealed that over half the teachers, 65.3% (n = 294), had never received any type of training in child sexual abuse education and that the majority were not familiar with methods of identifying child sexual abuse, 90.7% (n = 279). Various mistaken beliefs were identified among the participating teachers, such as pathological profiles of abusers, that the vast majority of child sexual abuse implies violent behavior, and that there cannot be abusers the same age as the victim. These results indicate that knowledge deficiencies do exist about child sexual abuse among teachers and highlight the need for training in this field.     

Analysis of Spanish policies for the integration of immigrant schoolchildren

The Organic Law on the Improvement of the National Education Quality (Ley Orgánica de Reforma de la Calidad Educativa) readdressed one of the most significant educational issues: educational policies related to immigrant students. Therefore, this is an appropriate moment to evaluate these types of policies in three singular Spanish regions: Madrid, Catalonia and Andalusia. This article presents an analysis of the measures taken in three Spanish regions: Madrid, Catalonia and Andalusia in response to students’ reception, acceptance and enrolment of immigrant students. A qualitative methodology based on the comparative method is used. Diverse similarities, but also specific characteristics and differences, can be found among the three models associated with each region. There are several significant differences that can be appreciated, such as the institutional role, as well as other specific measures. However, singular features are also identified, such as the diverse policies for the use of the vehicular language in each of the cases. Finally, the comparisons highlight various critical aspects, such as attention devoted to the students’ native language and progress towards intercultural education in school strategies and planning.     

Implementation of Jefferson-d’Hondt rule in the formation of a parliamentary committee

Same parliaments, to form a committee of size $q$ , use a voting process like the following: every parliamentary member votes for one out of a fixed set of candidates, and those $q$ candidates receiving more votes are elected for the committee. Assuming total discipline of vote, this is a game form in which players are the parliamentary groups. We investigate, according to some natural hypotheses about preferences, the likely distribution of the members of this committee. The main results are: (a) when fractional votes are allowed, there is a complete agreement between the distribution among the groups of the elected candidates that are outcomes of a Nash equilibrium and the distribution that, according to the size of the groups, would compute the Jefferson-d’Hondt allocation rule, and (b) when fractional votes are not allowed, there is a near agreement for a majority of situations.     

Preference intensity representation: strategic overstating in large elections

If voters vote strategically, is it useful to offer them the possibility of expressing nuanced opinions, or would they always overstate the intensity of their preferences? For additive voting rules, say that a ballot is extremal if it is neither abstention-like nor can be expressed as a mixture of the available ballots. We give a sufficient condition for strategic equivalence: if two rules share the same set of extremal ballots (up to an homothetic transformation), they are strategically equivalent in large elections. This condition is also necessary for the strategic equivalence of positional rules. These results do not hold for small electorates.     

Duration and Recurrence of Unemployment Benefits

Using administrative data for the period 2005–2010, we test for the existence of segmentation in the pool of the unemployed receiving benefits and investigate the factors associated with the duration and recurrence of the receipt of unemployment benefits in Spain. The results suggest the existence of (at least) three groups of individuals, each with different combinations of covered unemployment duration and recurrence. We also find that the impact of the employment crisis has been an increase in the average length of time spent receiving unemployment benefits and the recurrence. Our findings support the hypothesis that not only the heterogeneity but also the previous experience of receipt increase the expected duration of subsequent benefit periods.