Given a group G and an automorphism $\varphi $ of G, two elements $x,y\in G$ are said to be $\varphi $-conjugate if $x=gy\varphi (g)^{-1}$ for some $g\in G$. The number $R(\varphi )$ of equivalence classes with respect to this relation is called the Reidemeister number of $\varphi $ and the set $\{R(\varphi ) \mid \varphi \in \text {Aut}(G)\}$ is called the Reidemeister spectrum of G. We determine the Reidemeister spectrum of ZM-groups, extending some results of Senden [‘The Reidemeister spectrum of split metacyclic groups’, Preprint, 2022, arXiv:2109.12892].

In a recent paper, Juodis and Reese (2022, Journal of Business & Economic Statistics, 40, 1191–1203) (JR) show that the application of the CD test proposed by Pesaran (2004, General diagnostic tests for cross-sectional dependence in panels, CWPE 0435, Cambridge) to residuals from panels with latent factors results in over-rejection. They propose a randomized test statistic to correct for over-rejection, and add a screening component to achieve power. This article considers the same problem but from a different perspective and shows that the standard CD test remains valid if the latent factors are weak. A bias-corrected version, CD$^{\ast}$, is proposed which is shown to be asymptotically standard normal under the null of error cross-sectional independence which has power against network-type alternatives. This result is shown to hold for pure latent factor models as well as for panel regression models with latent factors. The case where the errors are serially correlated is also considered. Small sample properties of the CD$^{\ast}$ test are investigated by Monte Carlo experiments and are shown to have satisfactory small sample properties. In an empirical application, using the CD$^{\ast}$ test, it is shown that there remains spatial error dependence in a panel data model for real house price changes across 377 Metropolitan Statistical Areas in the United States, even after the effects of latent factors are filtered out.

The liberal order, as first articulated by Hobbes, depends upon an unnatural disembedding of both the economy and the polity from society. The economic and the political are keep apart. While the economy is seen as a private matter, the polity is conceived as a public one. The socially relational and mediating groups are squeezed out. Yet this involves contradiction. Is property primarily a matter of primary seizure or legal underwriting? Either the economic captures the political or vice-versa. A bad corporatism follows. The only alternative is a good corporatism recognising the priority of the social, of groups and their representation.

As America’s racial composition shifts, states that minimize changes to existing districts in successive redistricting cycles can entrench racial disparities in representation, a process I term dilutive drift. Using novel spatial measures of US House district change between successive congresses, I show that packing and cracking can occur passively, and not only through deliberate gerrymandering. States with long histories of racial exclusion, such as Alabama and Louisiana, make persistently fewer changes to their districts than other states. Minimal-change redistricting, I argue, can entrench unequal representation just as effectively as overt gerrymandering.

How do insights from environmental politics of the 1970s–1990s inform our understanding of contemporary climate governance? I suggest that the governance response for addressing pollution problems of the 1970s–1990s was sequential. The first wave of governance interventions addressed market failures; the second wave targeted government failures. In contrast, climate governance seeks to correct both market and government failures simultaneously. Furthermore, unlike first-generation environmental problems, domestic and international factors together hinder progress on climate change. Theoretically, this article examines how governance failures are recognized and addressed, how and why backlashes arise, and which governance innovations are possible in contested policy spaces. Three lessons emerge. First, governance innovations should be sculpted with failure drivers in mind. Because political challenges stall climate progress, climate policy must address these political concerns. Second, governance innovations cannot be expected to deliver a perfect solution devised by a technocratic elite. Policy progress is uneven, slow, and incremental. Third, governance arrangements, even on arguably highly technocratic issues, require social and political licenses to operate. Instead of asking the public to “listen to science,” climate-policy advocates should listen to people and devise policies that the public views as improving their everyday lives.

This article investigates crash risk premiums in individual stocks using skewness swaps. These swaps involve buying a stock’s risk-neutral skewness and receiving the realized skewness as a payoff. The strategy’s returns, which measure the skewness risk premium, are found to be consistently large and positive. This suggests investors are concerned about potential crashes in individual stocks and require substantial compensation for bearing this risk. Notably, significant results are mainly observed after the 2007/2009 financial crisis, indicating changes in post-crisis option market dynamics. Cross-sectional determinants of skewness swap returns include measures of systematic crash risk and stock overvaluation.

With rising environmental awareness, public attention has become an important external force shaping corporate green behaviour. Using Baidu search data to measure public green attention (PGA), this paper examines its impact on green technological innovation (GTI) among 1543 Chinese listed firms from 2011 to 2022. Employing a high-dimensional fixed-effects model, we find that PGA significantly promotes GTI, and the conclusion holds under alternative specifications. Heterogeneity analysis shows that this effect is stronger in firms and regions with more favourable conditions. Mechanism analysis indicates that PGA stimulates GTI mainly by strengthening environmental regulation, enhancing corporate social responsibility and reducing agency costs. Further analysis reveals that PGA-induced GTI leads to better Environmental, Social and Governance performance, lower business risk and improved operational outcomes. Overall, the results highlight the important role of public attention in advancing corporate green innovation and sustainability.

While Africa’s rapid urbanisation is expected to transform many aspects of political, economic and social life, decades of Africanist research shows that urban migration rarely severs rural ties. Building on this tradition, we use original survey data from 472 residents of Nairobi, Kenya, to examine how multiple forms of rural connection vary with urban duration and urban (re)orientation. We conceptualise four analytically distinct linkages – direct personal contact, provision of material support, anticipation of a rural safety net and spiritual connection – and measure each within a single empirical framework. We find that rural linkages do not diminish over time among first-generation migrants, but do decline across generations, with spiritual ties being especially persistent. Strong rural linkages are generally associated with weaker integration into urban social and political life. By disaggregating rural–urban connections and situating them in the temporal dynamics of urban residence, this article clarifies when and how African urbanisation transforms social and political orientations and provides a framework for cross-city and cross-country comparison.

The study provides a radiocarbon sequence for the Iron Age occupation in the elevated areas of the Phoenician settlement of Lisbon, located in the Tagus estuary (Portugal). The dataset is based in ten animal and human samples recovered during archaeological excavations at Largo de Santa Cruz do Castelo. These samples are associated with distinct phases of the Iron Age, dated by the ceramic findings between the 7th and 5th century BCE, as well as a latter sample from the Roman Republican Period (2nd half of the 2nd century BCE). Despite the challenges posed by the 1st millennium BCE radiocarbon calibration, this dataset proves valuable for establishing a more detailed chronological framework. It represents a significant contribution to refining the timeline of Lisbon’s Iron Age settlement and provides a stronger basis for interpreting local developments within the broader regional context.

In Paul of Aegina’s Pragmateia, the reading μυωτά for a type of short arrow has attracted scholarly attention. Das argued that an Arabic parallel supports the emendation μύωπα, but this has been questioned by Moseley. By looking at Graeco-Arabic translation technique, this short note shows that Das’s emendation μύωπα is probably right.