We develop explicit bounds for the tail of the distribution of the all-time supremum of a random walk with negative drift, where the increments have a truncated heavy-tailed distribution. As an application, we consider a ruin problem in the presence of reinsurance.

We use the framework of multivariate regular variation to analyse the extremal behaviour of preferential attachment models. To this end, we follow a directed linear preferential attachment model for a random, heavy-tailed number of steps in time and treat the incoming edge count of all existing nodes as a random vector of random length. By combining martingale properties, moment bounds and a Breiman type theorem we show that the resulting quantity is multivariate regularly varying, both as a vector of fixed length formed by the edge counts of a finite number of oldest nodes, and also as a vector of random length viewed in sequence space. A Pólya urn representation allows us to explicitly describe the extremal dependence between the degrees with the help of Dirichlet distributions. As a by-product of our analysis we establish new results for almost sure convergence of the edge counts in sequence space as the number of nodes goes to infinity.

One-fifth of the 101 million stroke survivors worldwide experience another stroke within the following five years. Research indicates that lifestyle risk factors account for 90% of stroke (similar to recurrent stroke) risk, and improving diet quality is a promising strategy(1). Synthesised research suggests that adopting a Mediterranean-style diet(2) with reduced sodium intake(3) can enhance cardiovascular health, which may be beneficial for secondary stroke prevention. Our previous ENAbLE trial, a co-designed telehealth diet and exercise intervention, demonstrated improvements in diet quality among stroke survivors. However, post-stroke effects (such as fatigue, hemiplegia, memory issues, aphasia, and dysphasia) along with poor culinary nutrition skills, limit the full adoption of the Mediterranean-style diet. Culinary nutrition combines cooking skills and nutrition knowledge to help individuals create nutritious and fulfilling meals. A recent scoping review revealed only two culinary nutrition programs designed for stroke survivors, with none co-designed specifically for Australian survivors. This research aims to co-design a Mediterranean-style diet based culinary nutrition program to enhance post-stroke nutrition. Using an Integrated Knowledge Translation model(4), three lived experience research partners and six clinical researchers engaged in the co-design process. Preliminary interviews with stakeholders highlighted gaps in current stroke care. We conducted two focus groups with potential end-users, including six stroke survivors and seven clinicians. Data were analysed thematically, and prototypes were developed iteratively with end-users. Consumers (lived experience research partners and end-users) identified a significant gap in practice during the early post-discharge period, emphasising the need for self-paced remote culinary nutrition resources. They identified several facilitators (e.g., simple recipes, easy translation of nutrition knowledge, aphasia-friendly design) and barriers (e.g., fatigue, muscle weakness, cooking for one or for a household) in meal preparation. Consumers noted that while recipe books reduce the cognitive load of meal preparation, no stroke-specific resources are currently available. As a result, we developed a co-designed recipe book titled Cook Well After Stroke, incorporating feedback from end-users. This book features Mediterranean-style diet recipes for both single-serving and household/batch cooking. It is designed with plain English, requiring minimal ingredients, equipment, and cooking skills. Recipes are highly adaptable to common Australian ingredients, encouraging users to repeat the recipes with available resources. It includes nutrition principles to create balanced meals, increase protein and vegetable intake, and reduce sodium consumption. Each section includes hints and hacks tailored to post-stroke effects, providing strategies for one-handed cooking, softer diet textures, and energy conservation. The recipe book will be integrated into a co-designed online cooking program, which will be trialled with stroke survivors.

In this paper we discuss laboratory experiments that address the problem of self-governance in an asymmetric commons dilemma. Small-scale irrigation systems that provide food for hundreds of millions of people around the world are probably the most common example of such dilemmas. Here, we formulate an abstract dilemma in which subjects make both a decision about investment in the provision of infrastructure associated with the use of a resource and about how much to extract from the common-pool resource made available by this infrastructure. The impact of inherent asymmetry in irrigation systems on the provision of a resource and the impact of communication on the capacity of the group to solve the two-level commons dilemma of cooperation and coordination based on the analysis of the experimental data are discussed.

A rich history of theoretical models in finance shows that speculation can lead to overpricing and price bubbles. We provide evidence that, indeed, individual speculative behavior fuels overpricing in (experimental) asset markets. In a first step, we elicit individual speculative behavior in a one-shot setting with a novel speculation elicitation task (SET). In a second step, we use this measure of speculative behavior to compose dynamic, continuous double auction markets in line with Smith et al. (Econometrica 56(5):1119–1151, 1988). We find significant higher overpricing in markets with traders who exhibited more speculative behavior in the individual SET. However, we find no such differences in overpricing when we test for alternative explanations, using a market environment introduced by Lei, Noussair, and Plott (Econometrica 69(4):831–859, 2001) where speculation is impossible. Taken together, our results corroborate the notion that speculation is an important factor in overpricing and bubble formation if market environments allow for the pursuit of capital gains.

When a response to a multiple-choice item consists of selecting a single-best answer, it is not possible for examiners to differentiate between a response that is a product of knowledge and one that is largely a product of uncertainty. Certainty-based marking (CBM) is one testing format that requires examinees to express their degree of certainty on the response option they have selected, leading to an item score that depends both on the correctness of an answer and the certainty expressed. The expected score is maximized if examinees truthfully report their level of certainty. However, prospect theory states that people do not always make rational choices of the optimal outcome due to varying risk attitudes. By integrating a psychometric model and a decision-making perspective, the present study looks into the response behaviors of 334 first-year students of physiotherapy on six multiple-choice examinations with CBM in a case study. We used item response theory to model the objective probability of students giving a correct response to an item, and cumulative prospect theory to estimate their risk attitudes when students choose to report their certainty. The results showed that with the given CBM scoring matrix, students’ choices of a certainty level were affected by their risk attitudes. Students were generally risk averse and loss averse when they had a high success probability on an item, leading to an under-reporting of their certainty. Meanwhile, they were risk seeking in case of small success probabilities on the items, resulting in the over-reporting of certainty.

In the course of the medical program at the University of Limburg, students complete a total of 24 progress tests, consisting of items drawn from a constant itembank. A model is presented for the growth of knowledge reflected by these results. The Rasch model is used as a starting point, but both ability and difficulty parameters are taken to be random, and moreover the logistic distribution is replaced by the normal. Both individual and group abilities are estimated and explained through simple linear regression. Application to real data shows that the model fits very well.

Open data promises various benefits, including stimulating innovation, improving transparency and public decision-making, and enhancing the reproducibility of scientific research. Nevertheless, numerous studies have highlighted myriad challenges related to preparing, disseminating, processing, and reusing open data, with newer studies revealing similar issues to those identified a decade prior. Several researchers have proposed the open data ecosystem (ODE) as a lens for studying and devising interventions to address these issues. Since actors in the ecosystem are individually and collectively impacted by the sustainability of the ecosystem, all have a role in tackling the challenges in the ODE. This paper asks what the contributions of open data intermediaries may be in addressing these challenges. Open data intermediaries are third-party actors providing specialized resources and capabilities to (i) enhance the supply, flow, and/or use of open data and/or (ii) strengthen the relationships among various open data stakeholders. They are critical in ensuring the flow of resources within the ODE. Through semi-structured interviews and a validation exercise in the European Union context, this study explores the potential contribution of open data intermediaries and the specific ODE challenges they may address. This study identified 20 potential contributions, addressing 27 challenges. The findings of this study pave the way for further inquiry into the internal incentives (viable business models) and external incentives (policies and regulations) to direct the contributions of open data intermediaries toward addressing challenges in the ODE.

Based on a new cored succession at Winterswijk, evidence is uncovered of the end-Triassic mass-extinction (ETME) event in a subsurface sedimentary succession of the Netherlands. The ETME was one of the most devastating events for the biosphere during the Phanerozoic era. Massive volcanism from the Central Atlantic Magmatic Province initiated the breakup of the supercontinent Pangea and resulted in terrestrial and marine extinction pulses, which drastically altered the course of life on Earth. The newly cored material reveals a sedimentary succession representing a shallow marine setting dominated by laminated black shale and claystone deposits. A high-resolution palynostratigraphic dataset provides evidence for a late Rhaetian vegetation assemblage that displays a stepwise decline of arborescent tree vegetation that is transiently replaced by a community of ferns and fern allies. Geochemical records link this major disturbance in palynofloral biodiversity to a pulse of volcanic activity as evidenced by a negative excursion in stable organic carbon isotopes. Shifts towards drier climate conditions, as inferred from sedimentary elemental composition, suggest continental aridification strongly influenced the terrestrial realm following volcanic pulses. Presence of reworked material suggests unstable soils that were affected by increased erosion rates, inhibiting the re-establishment of conifer tree vegetation. Comparison of our findings with other contemporaneous European Triassic-Jurassic boundary sections confirms the progression of the end-Triassic extinction, which exhibits a two-phased structure. The presence of the ETME in the subsurface of the Netherlands provides further evidence towards our understanding of terrestrial extinction with emphasis on the decline of vegetation.

This research explores the dynamic nature of family involvement in remote patient management for cardiovascular disease and its impact on lifestyle behaviour changes. Through an interview study with patients and family members, we categorise family involvement into three types: Inform, Integrate, and Influence, highlighting the dynamic and heterogeneous nature of family involvement across different phases and activities. Overall, we emphasise the need for personalised and adaptable interventions to cater to the diversity of families and propose a modular approach to remote monitoring design.

We examine financial literacy in Germany and its relevance for financial wellbeing. Using data from the Panel on Household Finances collected in 2021, we show that about 62% of German households answer the Big Three financial literacy questions correctly. Those with lower education, who are out of the labor force, women, and those living in East Germany have lower levels of financial literacy. Identifying groups with lower financial literacy and developing strategies to reach them and enhance their abilities should therefore be an integral part of the German national financial literacy strategy. Financial literacy is linked to financial wellbeing: we document that those with higher financial literacy have a higher stock market participation rate and are less likely to report financial difficulties.

The main cause of mortality in great apes in zoological settings is cardiovascular disease (CVD), affecting all four taxa: chimpanzee (Pan troglodytes), bonobo (Pan paniscus), gorilla (Gorilla spp.) and orangutan (Pongo spp.). Myocardial fibrosis, the most typical histological characterisation of CVD in great apes, is non-specific, making it challenging to understand the aetiopathogenesis. A multifactorial origin of disease is assumed whereby many potential causative factors are directly or indirectly related to the diet, which in wild-living great apes mainly consists of high-fibre, low-carbohydrate and very low-sodium components. Diets of great apes housed in zoological settings are often different compared with the situation in the wild. Moreover, low circulating vitamin D levels have recently been recognised in great apes housed in more northern regions. Evaluation of current supplementation guidelines shows that, despite implementation of different dietary strategies, animals stay vitamin D insufficient. Therefore, recent hypotheses designate vitamin D deficiency as a potential underlying factor in the pathogenesis of myocardial fibrosis. The aim of this literature review is to: (i) examine important differences in nutritional factors between zoological and wild great ape populations; (ii) explain the potential detrimental effects of the highlighted dietary discrepancies on cardiovascular function in great apes; and (iii) elucidate specific nutrition-related pathophysiological mechanisms that may underlie the development of myocardial fibrosis. This information may contribute to understanding the aetiopathogenesis of myocardial fibrosis in great apes and pave the way for future clinical studies and a more preventive approach to great ape CVD management.