A decisive voter’s exact ideological preferences can be hard to predict, even for seasoned candidates. We develop a novel theory of electoral competition where candidates are evaluated on ideological and nonideological dimensions. The key feature of our theory is that an electorate’s partisan leaning serves as a signal of the median voter’s ideological position where extreme leanings are more informative about voters than centrist leanings. We show that this leads to an endogenous sorting of districts between “extreme” and “centrist” and that an increase in the importance of candidate competence for voters increases polarization—but only in extreme districts. We evaluate our theory using data from mayoral elections in Brazil’s 95 largest municipalities and exploit COVID-19 as a shock to the salience of candidate competence. We show that COVID-19 increases the salience of competence in these elections, leading to increased political polarization, which is concentrated in cities with extreme partisan leanings.

While reformulation policies are commonly used to incentivise manufacturers to improve the nutrient profile of the foods and beverages they produce, only a few countries have implemented mandatory reformulation policies. This paper aimed to review evidence on the design, implementation challenges and effectiveness of mandatory reformulation policies and compare them to voluntary reformulation policies. The systematic search retrieved seventy-one studies including twelve on mandatory reformulation policies. Most mandatory reformulation policies were aimed at reducing trans-fatty acids or sodium in foods. Overall, mandatory reformulation policies were found to be more effective than voluntary ones in improving dietary intakes. Mandatory policies were implemented when voluntary policies either failed or were found to be insufficient to improve the composition of foods. Typical features of mandatory policies could also improve the design of voluntary policies. Examples include strict but attainable targets and a tight monitoring of compliance.

In this paper, we propose a hybrid sparse array design utilizing Delaunay Triangulation algorithm for element positioning and Convex algorithm for element excitation optimization. This Delaunay Triangulation algorithm yields a radiation pattern devoid of grating lobes. Then Convex algorithm is used to optimize the element excitations to further decrease side-lobe-level. The minimum inter-element distance is as large as 8 times of wavelength. The peak-side-lobe-level can be −17.3 dB. Furthermore, beam steering can be achieved with good performance within 80° field-of-view range.

This article documents a trend of declining flexibility in share repurchase policies over the last 4 decades. We show that repurchases have become particularly sticky for firms with repurchase programs in place. We also exploit the additional inflexibility within existing repurchase programs to show that repurchase stickiness can have real effects for firms. Using the 2008 financial crisis as a shock to firms’ ability to raise capital, we find that firms with ongoing share repurchase programs ending after Dec. 2007 reduced investment, employment, and R&D spending by more than similar firms with programs ending before the onset of the crisis.

Founded a century ago upon the initiative of three European men, each with links to colonial administration or mission, the International African Institute subsequently developed in directions that could hardly have been predicted. Most of those directly involved in the first two decades were from Belgium, Britain, France, Germany, Italy and Switzerland, including a growing number of academics. In addition to promoting creative writing in Africa and a common orthography for African languages, the Institute secured private American funding for a big research programme involving social anthropological fieldwork. After 1945, with decolonization on the horizon, the focus was on systematically producing ethnographic and linguistic handbooks. From the 1960s onwards the Institute endeavoured to shake off its remaining links to colonialism and – to a modest degree – to africanize itself. Its successes lay in organizing a series of International African Seminars, held at newly emerging African universities, and in continuing to produce the journal Africa, as well as several series of monographs.

The marketing of unhealthy foods has been implicated in poor diet and rising levels of obesity. Rapid developments in the digital food marketing ecosystem and associated research mean that contemporary review of the evidence is warranted. This preregistered (CRD420212337091)1 systematic review and meta-analysis aimed to provide an updated synthesis of the evidence for behavioural and health impacts of food marketing on both children and adults, using the 4Ps framework (Promotion, Product, Price, Place). Ten databases were searched from 2014 to 2021 for primary data articles of quantitative or mixed design, reporting on one or more outcome of interest following food marketing exposure compared with a relevant control. Reviews, abstracts, letters/editorials and qualitative studies were excluded. Eighty-two studies were included in the narrative review and twenty-three in the meta-analyses. Study quality (RoB2/Newcastle–Ottawa scale) was mixed. Studies examined ‘promotion’ (n 55), ‘product’ (n 17), ‘price’ (n 15) and ‘place’ (n 2) (some > 1 category). There is evidence of impacts of food marketing in multiple media and settings on outcomes, including increased purchase intention, purchase requests, purchase, preference, choice, and consumption in children and adults. Meta-analysis demonstrated a significant impact of food marketing on increased choice of unhealthy foods (OR = 2·45 (95 % CI 1·41, 4·27), Z = 3·18, P = 0·002, I2 = 93·1 %) and increased food consumption (standardised mean difference = 0·311 (95 % CI 0·185, 0·437), Z = 4·83, P < 0·001, I2 = 53·0 %). Evidence gaps were identified for the impact of brand-only and outdoor streetscape food marketing, and for data on the extent to which food marketing may contribute to health inequalities which, if available, would support UK and international public health policy development.

This article provides the first comprehensive evidence that the return extrapolation behavior of investors leads to biases in the expectations of volatility. Lower past returns are associated with higher expectations of volatility when using the physical, risk-neutral, and survey measures to estimate volatility expectations. Consistent with the return extrapolation framework, recent past returns have a larger impact than distant past returns on volatility expectations. Biases in volatility expectations are i) distinct from extrapolating past realized volatility, ii) asymmetrically induced by recent past negative returns, and iii) lead investors to pay more to insure against the perceived higher expected volatility.

We show theoretically and empirically that the cross-section of stock return idiosyncratic volatilities contains useful information about the ICAPM. We construct a proxy cross-sectional bivariate idiosyncratic volatility (CBIV) for the covariance risk between the market and the unobserved hedge portfolio under the ICAPM. Consistent with the ICAPM pricing relation, CBIV is a robust and significant predictor of the equity risk premium. We further show that the return predictability of the tail index in Kelly and Jiang (2014) can be explained by the ICAPM covariance risk.

Collaborative robotics in manufacturing introduces a new era of seamless human–robot collaboration (HRC), enhancing production line efficiency and adaptability. However, guaranteeing safe interaction while maintaining performance objectives presents significant challenges. Integrating safety with optimal robot performance is paramount to minimize task time and ensure its completion. Our work introduces an architecture for safety in confined human–robot workspaces by integrating existing safety and productivity methods into a unified framework specifically designed for constrained environments. By employing an improved artificial potential field, we optimize paths based on length and bending energy and compare baseline algorithms like gradient descent algorithm and rapidly exploring random tree (RRT*). We propose an evaluation metric for system performance that objectively maps to the system’s safety and efficiency in diverse collaborative scenarios. Additionally, the architecture supports multimodal interaction, including gesture-based inputs, for intuitive control and improved operator experience. Safety measures address static and dynamic obstacles using potential fields and safety zones, with a real-time safety evaluation module adjusting trajectories under specified constraints. A performance recovery algorithm facilitates swift resumption of high-speed operations post safety interventions. Validation includes comparing the algorithmic performance through simulations and experiments using the 6-degrees of freedom UR5 robot by universal robots to identify the most suitable algorithm. Results demonstrate an 83.87% improvement in system performance compared to ideal case scenarios, validating the effectiveness of the proposed architecture, evaluation metric, and multimodal interaction in enhancing safety and productivity.

The UK’s Health and Care Act (2022; paused until 2025) includes a globally novel ban on paid-for online advertising of food and beverage products high in saturated fat, salt and sugar (HFSS), to address growing concerns about the scale of digital marketing and its impact in particular on children’s food and beverage preferences, purchases and consumption. This study aimed to understand the potential impact of the novel ban (as proposed in 2020) on specified forms of online HFSS advertising, through the lens of interdisciplinary expertise. We conducted semi-structured interviews via videoconference with eight purposively selected UK and global digital marketing, food and privacy experts. We identified deductive and inductive themes addressing the policy’s scope, design, implementation, monitoring and enforcement through iterative, consensual thematic analyses. Experts felt this novel ‘breakthrough’ policy has potential to substantially impact global marketing by establishing the principle of no HFSS advertising online to consumers of all ages, but they also identified substantive limitations that could potentially render it ‘entirely ineffective’, for example, the exclusion of common forms of digital marketing, especially brand marketing and marketing integrated within entertainment content; virtual/augmented reality, and ‘advertainment’ as particularly likely spaces for rapid growth of digital food marketing; and technical digital media issues that raise significant barriers to effective monitoring and compliance. Experts recommended well-defined regulations with strong enforcement mechanisms. These findings contribute insights for effective design and implementation of global initiatives to limit online HFSS food marketing, including the need for government regulations in place of voluntary industry restrictions.

This article adopts a social constructivist approach to reinvestigate the Song-Liao relations that were manifested in the handscroll Eighteen Songs of a Nomad Flute 胡茄十八拍. Instead of offering a visual analysis of each of the 18 scenes in succession, it will point out the shared cultural practices and connotations of identity in the contrasting depictions of Song urban life and the nomad encampment. It argues that the handscroll probably represents the conservative faction's benevolent attitude towards nomadic tribes in the late Northern Song period, which is also likely to have been associated with the rise of Neo-Confucianism.

After a brief overview of Hans Zell’s publishing output, his own authorship, and that by others he published, I outline and assess his massive contribution to the bibliography and reference works of Africa, to African publishing and knowledge about it, and to associated networks and distribution in the North, as well as forays into the digital realm. In addition, I provide insights into his interaction with African studies librarians in the United States.

This study utilizes U.S. Patent Office data to explore potential improvements in the patent examination process through machine learning. It shows that integrating machine learning with human expertise can increase patent citations by up to 26%. Using machine learning predictions as benchmarks, I find that the early expiration rate of granted patents positively correlates with examiners’ false acceptance rates. These errors negatively impact public companies’ operational performance and reduce successful IPO or M&A exits for private firms. Overall, this study highlights significant social and economic benefits of incorporating machine learning as a robo-advisor in patent screening.