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The authors analyse the nature of nonlinear long-run causal dynamics between VIX futures and exchange-traded products (ETPs).

Nonlinear long-run causal relations between daily price movements in ETPs and futures are established through a Markov switching vector error correction model (MS-VECM).

The authors observe time variation in causality with the volatility of volatility. In particular, demand pressures for VIX ETNs and futures can change in different regimes. The authors observe two regimes where regime 1 is classified as low-mean low-volatility, while regime 2 is classified as high-mean high-volatility. The convergence to the long-run equilibrium in the low-mean low-volatility regime is faster than the high-mean high-volatility regime. The nature of the time varying lead lag relations demonstrates the opportunities for arbitrage.

The linear causal relations between VXX and VIX futures are well established, with leads and lags generally found to be short-lived with arbitrage relations holding. The authors go further to capture the time-varying causal relationships through a Markovian process. The authors establish the nonlinear causal relations between inverse and leveraged products where causal relations are not yet documented.

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.

This review investigates the effects of temporal aggregation and systematic sampling on time-series analysis, focusing on their influence on data accuracy, interpretability and statistical properties. The purpose of the study is to synthesise existing literature on the topic and offer insights into the trade-offs between these data reduction techniques.

The research methodology is based on an extensive review of theoretical and empirical studies covering univariate and multivariate time series models, focusing on unit roots, ARIMA, GARCH, cointegration properties and Granger Causality.

The key findings reveal that while temporal aggregation simplifies data by emphasising long-term trends, it can obscure short-term fluctuations, potentially leading to biases in analysis. Similarly, systematic sampling enhances computational efficiency but risks information loss, especially in non-stationary data, and may result in biased samples if sampling intervals coincide with data periodicity. The review highlights the complexities and trade-offs involved in applying these methods, particularly in fields like economic forecasting, climate modelling and financial analysis.

The originality and value of this study lie in its comprehensive synthesis of the impacts of these techniques across various time series properties. It underscores the importance of context-specific applications to preserve data integrity, offering recommendations for best practices in the use of temporal aggregation and systematic sampling in time-series analysis.

Although legislation and regulations form an important foundation for recordkeeping and for accountability, questions of transparency and openness must be addressed in a wider context. Oliver and Foscarini have argued for the importance of recognising differing cultures and the ways in which they value records and recordkeeping. In addition to reporting mechanisms and relationships, accountability must encompass a culture and a mindset which is transparent, responsive and focused on self-improvement. This paper aims to apply a dual interpretation of accountability in the context of Irish public sector recordkeeping to identify shortcomings and suggest potential remedies with a view to improving the accountability of Irish recordkeeping itself, and the extent to which it contributes to wider accountability in society.

This paper assesses accountability in Irish public sector recordkeeping using a model suggested by Mark Bovens, which views accountability as both a mechanism and a virtue. The model emphasises that both interpretations are necessary but that mechanisms (laws, regulations and checklists) on their own cannot be sufficient to satisfy accountability requirements. As noted by Onora O’Neill, the aim of accountability should not be checklists or artificial metrics, but the nurturing of behaviours and cultures which make public institutions more deserving of our trust. Reference will be made to Irish legislation, to records management policies in government departments, to relevant annual reports and to current practice with regard to appraisal and other recordkeeping functions to measure Irish public sector recordkeeping against Bovens' model.

This paper suggests that Irish public sector recordkeeping has a range of shortcomings under both the narrow (mechanism) and broad (virtue) interpretations of accountability. Lack of reporting requirements and oversight mechanisms in existing legislation allows for major gaps in public sector recordkeeping, facilitating a lack of accountability in the citizen–state relationship. Meanwhile, an absence of records management policies and an overall lack of appreciation of the value of records leads to opaque practices and a lack of transparency. The recordkeeping profession itself adopts processes and practices, which are not aligned with the concept of accountability as a virtue, and which do not reflect a commitment to transparency and meeting the legitimate interests of stakeholders. This paper suggests changes in relevant legislation but also suggests that these must be accompanied by a more open and responsive working culture within the recordkeeping profession.

By applying Bovens’ dual concept of accountability, this paper provides a new and more comprehensive assessment of public sector recordkeeping in Ireland, which can equally be applied in other contexts. It identifies ways in which revised legislation can contribute to greater accountability, but emphasises that regulations must be accompanied by a culture of transparency and responsiveness, and that recordkeepers have a crucial role to play in terms of their own commitment to transparency and professional accountability.

The purpose of the present study was twofold: (1) to examine the direct effect of the dimensions of opportunity (i.e. ethical climate and institutional policy) and dimensions of job pressure (i.e. workload and work pressure) on workplace deviance (i.e. organisational and interpersonal deviance) and (2) to assess the mediation of neutralisation in the relationship between the dimensions of opportunity, job pressure and workplace deviance.

The present study drew from the fraud triangle theory (FTT; Cressey, 1950) and the theory of neutralisation (Sykes and Matza, 1957) to achieve the research objectives. Survey data from 356 full-time faculty members in Nigerian public universities were collected. Partial least square-structural equation modelling (PLS-SEM) was employed to analyse the data.

The results indicated that opportunity and job pressure significantly affected workplace deviance. As expected, neutralisation was found to mediate the negative relationship between ethical climate and interpersonal deviance and the positive relationship between workload, work pressure and interpersonal deviance. Contrary to expectation, neutralisation did not mediate the relationship between opportunity, pressure and organisational deviance.

The sample was drawn from academics in public universities and the cross-sectional nature of this study means that the findings have limited generalisations.

This study offers insights into the management of Nigerian public universities on the need to curb workplace deviance amongst faculty members. This study recommends that the management improve the work environment by enhancing the ethical climate and institutional policies and reviewing the existing workload that may constitute pressure to the faculty members.

The present study provides empirical support for the fraud triangle theory and theory of neutralisation to explain workplace deviance.

The paper follows Jason Cope's (2011) vision of a holistic perspective on the failure-based learning process. By analyzing the research since Cope's first attempt, which is often fragmentary in nature, and providing novel empirical insights, the paper aims to draw a new comprehensive picture of all five phases of entrepreneurial learning and their interplay.

The study features an interpretative phenomenological analysis of in-depth interviews with 18 failed entrepreneurs. Findings are presented and discussed in line with experiential learning theory and Cope's conceptual framework of five interrelated learning timeframes spanning from the descent into failure until re-emergence.

The study reveals different patterns of how entrepreneurs experience failure, ranging from abrupt to gradual descent paths, different management and coping behaviors, and varying learning effects depending on the new professional setting (entrepreneurial vs non-entrepreneurial). Analyzing the entrepreneurs' experiences throughout the process shows different paths and connections between individual phases. Findings indicate that the learning timeframes may overlap, appear in different orders, loop, or (partly) stay absent, indicating that the individual learning process is even more dynamic and heterogeneous than hitherto known.

The paper contributes to the field of entrepreneurial learning from failure, advancing Cope's seminal work on the learning process and -contents by providing novel empirical insights and discussing them in the light of recent scientific findings. Since entrepreneurial learning from failure is a complex and dynamic process, using a holistic lens in the analysis contributes to a better understanding of this phenomenon as an integrated whole.

Peduncluar hallucinosis is a rare neurological disorder characterized by visual hallucinations, often described to be vivid and dream-like. While the exact pathophysiology has yet to be elucidated, most cases to date have suggested an etiology stemming from lesions to the thalamus or midbrain. Here presented is a case of a 54-year-old female with peduncular hallucinosis secondary to a pontine cavernoma hemorrhage in the setting of essential hypertension. The patient's vivid visual and auditory hallucinations aligned temporally with the lesion's discovery and resolved after pharmaceutical treatment. This case represents a rare form of peduncular hallucinosis secondary to a pontine cavernoma hemorrhage leading to vasospasm in the arteries feeding the brainstem.

The 30 MOCHA (Models of Child Health Appraised) countries are diverse socially, culturally and economically, and differences exist in their healthcare systems and in the scope and role of primary care. An economic analysis was undertaken that sought to explain differences in child health outcomes between countries. The conceptual framework was that of a production function for health, whereby health outputs (or outcomes) are assumed affected by several ‘inputs’. In the case of health, inputs include personal (genes, health behaviours) and socio-economic (income, living standards) factors and the structure, organisation and workforce of the healthcare system. Random effects regression modelling was used, based on countries as the unit of analysis, with data from 2004 to 2016 from international sources and published categorisations of healthcare system. The chapter describes the data deficiencies and measurement conundrums faced, and how these were addressed. In the absence of consistent indicators of child health outcomes across countries, five mortality measures were used: neonatal, infant, under five years, diabetes (0–19 years) and epilepsy (0–19 years). Factors found associated with reductions in mortality were as follows: gross domestic product per capita growth (neonatal, infant, under five years), higher density of paediatricians (neonatal, infant, under five years), less out-of-pocket expenditure (neonatal, diabetes 0–19), state-based service provision (epilepsy 0–19) and lower proportions of children in the population, a proxy for family size (all outcomes). Findings should be interpreted with caution due to the ecological nature of the analysis and the limitations presented by the data and measures employed.

Drawing on the discursive properties of placemaking theory, this paper discusses the development of film tourism in Crete from the release of the award-winning Zorba the Greek (dir. Michael Cacoyannis, ZG) to date. The approach is “genealogical,” seeking to explain how ZG-inspired tourism on Crete ended up being more than about the film itself owing to historical contingency.