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Factor investment is booming in global asset management, especially environmental, social, and governance (ESG), dividend yield, and volatility factors. In this chapter, we use data from the US securities market from 2003 to 2019 to predict dividends and volatility factors through machine learning and historical data–based methods. After that, we utilize particle swarm optimization to construct the Markowitz portfolio with limits on the number of assets and weight restrictions. The empirical results show that that the prediction ability using XGBoost is superior to the historical factor investment method. Moreover, the investment performance of our portfolio with ESG, high-yield, and low-volatility factors outperforms baseline methods, especially the S&P 500 ETF.

In this article, we use the film Bridge of Spies – which depicts the case of U-2 spy pilot Francis Gary Powers – and relevant primary sources, particularly Powers' letters from prison, to provide teachers with a case that can engage students with the complexity of the Cold War. Understanding USA–Russia relations is as important today as ever as we watch the tragedy unfold in Ukraine. Using primary sources to reflect on the Cold War can help secondary students understand the historical context of the war in Ukraine as well as how to evaluate and critique sources of information about the war.

The film and personal letters provide insights often not available or obvious when we focus on the political or military history of an event or time period. The Cold War is frequently defined by the rhetoric of the USA and Union of Soviet Socialist Republics (USSR) governments – but everyday people and citizens had a wider range of views and experiences. The film and letters bring out the humanity of the Cold War.

This article supports secondary teachers in incorporating film and primary sources as teaching tools to study the Cold War while more broadly thinking about these sources as ways to understand the past. The letters used, including those from U-2 spy pilot Francis Gary Powers, help us understand his time in a Soviet prison as well as the behind-the-scenes work to free him as part of a prisoner exchange.

The U-2 Incident and other events of the Cold War provide important context for understanding the Cold War-like tensions between the USA and Russia today. The distrust between these countries has a long history. However, documents like the film and letters discussed here show that there is much more to the bluster of political leaders and the military chess game. There is an important human element to these events and an impact on individuals who are much more than pawns in international diplomacy.

This study presents a systematic literature review (SLR) of the interdisciplinary literature on drones in last-mile delivery (LMD) to extrapolate pertinent insights from and into the logistics management field.

Rooting their analytical categories in the LMD literature, the authors performed a deductive, theory refinement SLR on 307 interdisciplinary journal articles published during 2015–2022 to integrate this emergent phenomenon into the field.

The authors derived the potentials, challenges and solutions of drone deliveries in relation to 12 LMD criteria dispersed across four stakeholder groups: senders, receivers, regulators and societies. Relationships between these criteria were also identified.

This review contributes to logistics management by offering a current, nuanced and multifaceted discussion of drones' potential to improve the LMD process together with the challenges and solutions involved.

The authors provide logistics managers with a holistic roadmap to help them make informed decisions about adopting drones in their delivery systems. Regulators and society members also gain insights into the prospects, requirements and repercussions of drone deliveries.

This is one of the first SLRs on drone applications in LMD from a logistics management perspective.

This study is the first to investigate the causal relationship between Bitcoin and equity price returns by sectors. Previous studies have focused on aggregated indices such as S&P500, Nasdaq and Dow Jones, but this study uses mixed frequency and disaggregated data at the sectoral level. This allows the authors to examine the nature, direction and strength of causality between Bitcoin and equity prices in different sectors in more detail.

This paper utilizes an Unrestricted Asymmetric Mixed Data Sampling (U-AMIDAS) model to investigate the effect of high-frequency Bitcoin returns on a low-frequency series equity returns. This study also examines causality running from equity to Bitcoin returns by sector. The sample period covers United States (US) data from 3 Jan 2011 to 14 April 2023 across nine sectors: materials, energy, financial, industrial, technology, consumer staples, utilities, health and consumer discretionary.

The study found that there is no causality running from Bitcoin to equity returns in any sector except for the technology sector. In the tech sector, lagged Bitcoin returns Granger cause changes in future equity prices asymmetrically. This means that falling Bitcoin prices significantly influence the tech sector during market pullbacks, but the opposite cannot be said during market rallies. The findings are consistent with those of other studies that have established that during market pullbacks, individual asset prices have a tendency to decline together, whereas during market rallies, they have a tendency to rise independently. In contrast, this study finds evidence of causality running from all sectors of the equity market to Bitcoin.

The findings have significant implications for investors and fund managers, emphasizing the need to consider the asymmetric causality between Bitcoin and the tech sector. Investors should avoid excessive exposure to both Bitcoin and tech stocks in their portfolio, as this may lead to significant drawdowns during market corrections. Diversification across different asset classes and sectors may be a more prudent strategy to mitigate such risks.

The study's findings underscore the need for investors to pay close attention to the frequency and disaggregation of data by sector in order to fully understand the true extent of the relationship between Bitcoin and the equity market.

Stalking is considered a public health priority with a range of adverse outcomes. This paper aims to explore existing literature on children and adolescents as perpetrators of stalking, with a focus on rates of stalking and victim and perpetrator characteristics associated with stalking.

A review of research where stalking was engaged in by those 18 years old and younger was conducted, where 17 manuscripts met criteria for review.

This review found a prevalence of young people engaging in stalking of between 5.3% and 36%. Considerations including demographics, typologies, prior relationship characteristics, stalking and pursuit tactics, cyberstalking and a brief consideration of the impact are given.

Literature considering perpetration remains thin, and future research should seek to move towards a widely acceptable definition of stalking, as well as considering effective interventions for early intervention, and to consider the role of mental health services in supporting perpetrators and victims, who may not always be mutually exclusive groups.

This paper extends previous literature reviews; the authors understand this to be original work that contributes to a gap in the literature.

The authors analyse six actively traded VIX Exchange Traded Products (ETPs) including 1x long, −1x inverse and 2x leveraged products. The authors assess their impact on the VIX Futures index benchmark.

Long-run causal relations between daily price movements in ETPs and futures are established, and the impact of rebalancing activity of leveraged and inverse ETPs evidenced through causal relations in the last 30 min of daily trading.

High frequency lead lag relations are observed, demonstrating opportunities for arbitrage, although these tend to be short-lived and only material in times of market dislocation.

The causal relations between VXX and VIX Futures are well established with leads and lags generally found to be short-lived and arbitrage relations holding. The authors go further to capture 1x long, −1x inverse as well as 2x leveraged ETNs and the corresponding ETFs, to give a broad representation across the ETP market. The authors establish causal relations between inverse and leveraged products where causal relations are not yet documented.

Railways are a well-known example of complex critical infrastructure, incorporating socio-technical systems with humans such as drivers, signallers, maintainers and passengers at the core. The technological evolution including interconnectedness and new ways of interaction lead to new security and safety risks that can be realised, both in terms of human error, and malicious and non-malicious behaviour. This study aims to identify the human factors (HF) and cyber-security risks relating to the role of signallers on the railways and explores strategies for the improvement of “Digital Resilience” – for the concept of a resilient railway.

Overall, 26 interviews were conducted with 21 participants from industry and academia.

The results showed that due to increased automation, both cyber-related threats and human error can impact signallers’ day-to-day operations – directly or indirectly (e.g. workload and safety-critical communications) – which could disrupt the railway services and potentially lead to safety-related catastrophic consequences. This study identifies cyber-related problems, including external threats; engineers not considering the human element in designs when specifying security controls; lack of security awareness among the rail industry; training gaps; organisational issues; and many unknown “unknowns”.

The authors discuss socio-technical principles through a hexagonal socio-technical framework and training needs analysis to mitigate against cyber-security issues and identify the predictive training needs of the signallers. This is supported by a systematic approach which considers both, safety and security factors, rather than waiting to learn from a cyber-attack retrospectively.

This paper aims to understand employees’ propensity to blow the whistle in two East African countries. This study develops a model of ethical decision-making (EDM) to assist management in predicting the probability of whistleblowing in Kenya and Uganda. It also seeks to find the moderating effect of perceived retaliation on whistleblowing intention.

This study administers a standardized questionnaire to employees in Kenya and Uganda to measure their perceptions about whistleblowing in their organizations. This study uses partial least square structural equation modeling to test the hypotheses. This study uses four constructs, namely, awareness, judgment, retaliation and likelihood, of blowing the whistle. These constructs are measured with multiple-item scales.

The results show that ethical awareness and judgment significantly increase willingness to engage in whistleblowing in East Africa. However, this study does not find a significant retaliation effect on whistleblowing intention. Instead, this study finds that awareness and judgment mediate between retaliation and willingness to engage in whistleblowing.

This study contributes to EDM topics. It advances the understanding of the whistleblowing concept, the retaliation effect and the reasons to encourage blowing the whistle in Africa. However, this study did not consider cultural factors, such as nationality, patriotism and ethnicity. Moreover, the results are only based on data from Uganda and Kenya and may not apply to other sub-Saharan nations.

These findings are particularly significant for managers and policymakers in East Africa, where fear of retaliation and lack of awareness are the main barriers to whistleblowing. The results may help managers develop human resource practices to include policies to support moral behavior. It may also provide insights to the policymakers to understand the factors that facilitate whistleblowing practices and help them to adopt new strategies or policies to stimulate whistleblowing culture.

This study is one of the initial empirical studies in the East Africa context to explore the EDM predictors and the impact of retaliation on the whistleblowing intention.

Teachers are an adaptive group of professionals and in this chapter, we explore the ways that teachers can develop themselves as leaders, even in the absence of strong support or leadership. We explore the manner that these skill sets and strengths can be cultivated, providing lived examples of how the authors have developed themselves. The ways that teachers can follow in the footsteps of the authors is outlined in clearly defined steps. By drawing on previous literature, we provide seven strong claims of developing middle leadership knowledge and skill sets beyond your school. Much of this development and community development work that develops and sharpens leadership skills can be explored through online fora and social media tools. These tools allow skill development, professional learning, and exposure to a broad range of education stakeholders and groups; for future pathways in school leadership roles and leading beyond school gate.

This study investigated the relationship between principals' abusive leadership and teachers' intrinsic and extrinsic motivations, exploring the potential moderating effects of the duration of the relationship and group size within educational settings.

Data were collected from a sample of teachers in Bahrain, using self-report measures. The data were analyzed using regression analyses.

The findings reveal a significant negative relationship between principals' abusive leadership and teachers' intrinsic and extrinsic motivations. The results also show that the duration of the relationship moderates the correlation between abusive leadership and teachers' extrinsic motivation, with teachers who have been in longer relationships with their principals showing greater resistance to the detrimental effects of abusive leadership on their extrinsic motivation. Group size was found to moderate this correlation, with larger groups exhibiting stronger buffering against the negative effect of abusive leadership.

The findings provide valuable insights into the dynamics of abusive leadership in educational settings and the potential moderating factors that can help alleviate its detrimental effects on teachers' motivations.