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A hyperplane arrangement is called formal provided all linear dependencies among the defining forms of the hyperplanes are generated by ones corresponding to intersections of codimension two. The significance of this notion stems from the fact that complex arrangements with aspherical complements are formal. The aim of this note is twofold. While work of Yuzvinsky shows that formality is not combinatorial, in our first main theorem we prove that the combinatorial property of factoredness of arrangements does entail formality. Our second main theorem shows that formality is hereditary, i.e., is passed to restrictions. This is rather counter-intuitive, as in contrast the known sufficient conditions for formality, i.e., asphericity, freeness and factoredness (owed to our first theorem), are not hereditary themselves. We also demonstrate that the stronger property of k-formality, due to Brandt and Terao, is not hereditary.

Olympic event zones are characterized as being intensely formally regulated during live staging periods, producing exclusionary environments blamed for sidelining host community interests. Yet, our findings contradict what scholars perceive to be inflexible formal regulations, and, the regulator's ability to take informal action. By interviewing and drawing on the experience of 17 regulators during London 2012 we identify how regulators simultaneously oscillate between modes of regulatory formality and informality, straddling what is referred to as the \"formality-informality span.\" Our application and theorization of these concepts critiques existing explanations of how regulation is enacted in mega-sporting events, providing new insights into the way organizers balance regulatory demands and potentially opening up new emancipatory policies and more equitable outcomes for host communities.

Olympic event zones are characterised as being intensely formally regulated during live staging periods, producing exclusionary environments blamed for side-lining host community interests. Yet, our findings contradict what scholars perceive to be inflexible formal regulations, and, the regulator’s ability to take informal action. By interviewing and drawing on the experience of 17 regulators during London 2012 we identify how regulators simultaneously oscillate between modes of regulatory formality and informality, straddling what is referred to as the ‘formality-informality span’. Our application and theorisation of these concepts critiques existing explanations of how regulation is enacted in mega-sporting events, providing new insights into the way organisers balance regulatory demands and potentially opening up new emancipatory policies and more equitable outcomes for host communities.

Researchers primarily focus on the formal practices used by event organisers to establish temporary spaces like Host Event Zones, characterised as a unilateral process that ignores community interests. Yet little research investigates both the formal and informal interactions between stakeholders. Interviews with London 2012 senior organisers after the ‘fog of organising’ has lifted – and without political pressure to toe-the-line – reveals how two-way dialogue was facilitated through various communicative mechanisms, from ‘road shows’ to more inclusive Olympic Organising Committee meetings. This counters previous arguments and contributes new knowledge by revealing – and more accurately representing - how event zones are co-created through negotiation between the event and community. Consequently, scholars should be wary of extrapolating from formal practices on paper and interrogate the more complex and messy informalities of planning to improve veracity of claim(s).

In recent years, scholars in migration, urban studies, and urban planning have increasingly focused on the diversity of arrival processes experienced by international newcomers and the variety of spatial settings they involve. Current research on arrival infrastructures focuses on both place-based opportunity structures and newcomers’ agency in shaping arrival processes, illustrating the interconnectedness of formal and informal infrastructures. Arrival infrastructuring can be understood as a mediating process that connects individuals and their social, economic, and cultural capital to places and societal resources. The concept of “in/formality,” which addresses the formal–informal nexus as a continuum rather than in binary terms, offers a valuable yet underexplored perspective to analyse arrival processes and actors involved, including the state, market, and old and new residents. Through the lens of in/formality, this thematic issue aims to explore the practices, negotiations, and interconnections among different (migrant and non-migrant) actors involved in arrival infrastructuring. The contributions highlight four recurring ways in which the interplay between informal and formal practices manifests: unusual alliances, brokering, boundary spanning, and structured workarounds.

This study offers a systematic comparison of automated content analysis tools. The ability of different lexicons to correctly identify affective tone (e.g., positive vs. negative) is assessed in different social media environments. Our comparisons examine the reliability and validity of publicly available, off-the-shelf classifiers. We use datasets from a range of online sources that vary in the diversity and formality of the language used, and we apply different classifiers to extract information about the affective tone in these datasets. We first measure agreement (reliability test) and then compare their classifications with the benchmark of human coding (validity test). Our analyses show that validity and reliability vary with the formality and diversity of the text; we also show that ready-to-use methods leave much space for improvement when analyzing domain-specific content and that a machine-learning approach offers more accurate predictions across communication domains.

Researchers primarily focus on the formal practices used by event organizers to establish temporary spaces like Host Event Zones, characterized as a unilateral process that ignores community interests. Yet little research investigates both the formal and informal interactions between stakeholders. Interviews with London 2012 senior organizers after the \"fog of organizing\" has lifted-and without political pressure to toe-the-line-reveals how two-way dialogue was facilitated through various communicative mechanisms, from \"road shows\" to more inclusive Olympic Organizing Committee meetings. This counters previous arguments and contributes new knowledge by revealing-and more accurately representing-how event zones are cocreated through negotiation between the event and community. Consequently, scholars should be wary of extrapolating from formal practices on paper and interrogate the more complex and messy informalities of planning to improve veracity of claim(s).

This study explored the compliment response (CR) strategies used by Emirati Arabic speakers. In addition, the study analysed the role of gender and the degree of formality in the use of CR strategies in this Arabic dialect. To this end, the study recruited 56 (28 males and 28 females) undergraduate students from the University of Sharjah (UAE). A written discourse completion task (DCT) consisting of 10 (five formal and five informal) scenarios was used to elicit CRs from the participants. The results showed that the Emiratis’ most frequently used major strategy is the Acceptance strategy, with Returning the Compliment and Expressing Gratitude being the most used sub-strategies and Agreeing and Encouraging being the least frequently used. The study shows that variations in the construction and realisation of speech acts exist due to gender and degree of formality. In particular, although both genders made use of the same major strategy, they showed differences in the use of the sub-strategies according to the (in)formality of the situation.

We develop a theory of minimal models for algebras over a Koszul operad with trivial differential defined over a commutative ring (containing $\\mathbb {Q}$ in the symmetric case), not necessarily a field, extending and supplementing the work of Sagave for the associative case. Our minimal models are bigraded and contain a projective resolution of the homology.

A Riemannian metric on a closed manifold is said to be geometrically formal if the wedge product of any two harmonic forms is harmonic; equivalently, the interior product of any two harmonic forms is harmonic. Given a Riemannian foliation on a closed manifold, we say that a bundle-like metric is transversely geometrically formal if the interior product of any two basic harmonic forms is basic harmonic. In this paper, we examine the geometric and topological consequences of this condition.