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The purpose of this article is to consider the classical risk model that is perturbed by a Brownian motion process. The article derives explicit formulas for the joint and marginal probability density functions of the surplus prior to ruin and the deficit at ruin.

This article first extends the dual argument to probabilistically explain the symmetry between the two random variables related to the so‐called modified ladder height. Then the paper uses renewal arguments to derive the joint distribution of the surplus prior to ruin and the deficit at ruin.

The study derived an explicit formula for the undiscounted joint density in the perturbed risk model that is directly parallel to formula (3.2) for the classical risk model. The formula clearly shows that in a perturbed risk process, when ruin is caused by a claim, the p.d.f. of the surplus prior to ruin is continuous. In addition, shows that when the claim sizes follow a phase‐type distribution, all the relevant quantities can be conveniently computed.

The dual argument used in this article is novel. The formula first clearly shows that in the perturbed risk model, the p.d.f. of the surplus prior to ruin is continuous. When claim sizes are phase‐type, the formulas can be conveniently computed.

The paper discusses ethical issues related to the adaptive reuse of ruin heritage on the example of the so-called ruin bars in Budapest's District VII. It explores how heritage discourse can contribute to the sustainable development of urban neighborhoods. The authors address the question by focusing on how a processual approach can be instrumental in identifying responsible and socially sustainable ways to reuse dilapidated heritage in a residential area.

The problem is analyzed through a case study based on field observation, participant observation, stakeholder interviews, policy analysis and media and social media content analysis.

The authors argue that ethical reuse of ruin heritage must take into consideration the values and interests of multiple stakeholders and the broadest range of consequences at the level of neighborhood and city. An integrated heritage and planning policy should consider and involve as active participants all the heritage communities concerned. Importantly, these groups, comprising both new and longtime residents, must include the vulnerable and marginalized.

The findings can be used by heritage managers for identifying and addressing ethical issues in their adaptive heritage reuse practices and by policymakers for integrating heritage management in urban development and making cities more inclusive (SDG #11).

The paper explores how ethical it is for business enterprises to build on the ruin esthetics in a residential district and what the ethical implications of this reuse process are for various stakeholders.

Despite the increasing academic interest for urban ruins and evolutions of urban tourism, research on ruin tourism as an emergent form of urban tourism practice is still lacking. Drawing on existing works on urban exploration, the purpose of this paper is to provide a first geographical insight into ruin tourism and its spatial implications in terms of imaginaries, practices and regulation of urban space.

Drawing on an urban and cultural geography approach, the research is based on a mix of empirical methodologies. Participant observation of organized ruin tours as well as formal and informal interviews with participants, organizers, institutional actors and inhabitants have been conducted during fieldwork completed in Berlin and Detroit. This paper also draws on the analysis of additional data provided by online material, especially official websites of tour organizers, forum threads and comments posted on different websites.

The research shows that ruin tourism can be analyzed as a new practice of urban tourism based on the reappropriation and commodification of alternative practices developing in marginalized urban areas. The paper provides evidence of ruin tourism’s contribution to the normalization of urban space through tourism conquest of new urban territories. It also shows that the practice fosters contested material and symbolic appropriations of place.

This paper contributes to current research on alternative tourism practices in marginalized urban areas as well as on tourist appropriation of liminal spaces. It provides a first analysis of ruin tourism and underscores its potential as a geographical object for the investigation of a wide range of urban issues.

The purpose of this paper is to study how the discretization interval affects the solvency measurement of a property-liability insurance company.

Starting with a basic solvency model, the authors study the impact of the discretization interval on risk measures. The analysis considers the sensitivity of the discrepancy between the risk measures in continuous and discrete time to various parameters, such as the asset-to-liability ratio, the characteristics of the asset and liability processes, as well as the correlation between assets and liabilities. Capital requirements for the one-year planning horizon in continuous vs discrete time are reported as well. The purpose is to report the degree to which the deviations in risk measures, due to the different discretization intervals, can be reduced by means of increasing the frequency with which the risk measures are assessed.

The simulation results suggest that the risk measures of an insurance company are consistently underestimated when assessed on an annual basis (as it is currently done under insurance regulation such as Solvency II). The authors complement the analysis with the capital requirements of an insurance company and conclude that more frequent discretization translates into higher capital requirements for the insurance company. Both the probability of ruin and the expected policyholder deficit (EPD) can be reduced through intermediate financial reports.

The results from our simulation analysis suggest that that the choice of discretization interval has an impact on the risk assessment of an insurance company which uses the probability of ruin and the EPD as risk measures. By assessing the risk measures once a year, both risk measures and the capital requirements are consistently underestimated. Therefore, the recommendation for risk managers is to complement the capital requirements in solvency regulation with sensitivity analyses of the risk measures presented with respect to time discretization. On the one hand, it seems to us that there is value in knowing about the substantial discrepancy between the focused time discrete ruin probability and EPD compared to the continuous version. On the other hand, and if there are no substantial transaction costs associated with more frequent monitoring of solvency figures, a frequent update would be helpful to increase the accuracy of the calculations and reduce the EPD.

The concept of value at risk is used in the risk-based calculation of solvency capital requirements in the Basel II/III banking regulations and in the planned Solvency II insurance regulation framework planned in the European Union. While this measure controls the ruin probability of a financial institution, the expected policyholder deficit (EPD) and expected shortfall (ES) measures, which are relevant from the customer's perspective as they value the amount of the shortfall, are not controlled at the same time. Hence, if there are variations in or changes to the asset-liability situation, financial companies may still comply with the capital requirement, while the EPD or ES reach unsatisfactory levels. This is a significant drawback to the solvency frameworks. The paper aims to discuss these issues.

The author has developed a model framework wherein the author evaluates the relevant risk measures using the distribution-free approach of the normal power approximation. This allows the author to derive analytical approximations of the risk measures solely through the use of the first three central moments of the underlying distributions. For the case of a reference insurance company, the author calculates the required capital using the ruin probability and EPD approaches. For this, the author performs sensitivity analyses considering different asset allocations and different liability characteristics.

The author concludes that only a simultaneous monitoring of the ruin probability and EPD can lead to satisfactory results guaranteeing a constant level of customer protection. For the reference firm, the author evaluates the relative changes in the capital requirement when applying the EPD approach next to the ruin probability approach. Depending on the development of the assets and liabilities, and in the cases the author illustrates, the reference company would need to provide substantial amounts of additional equity capital.

A comparative assessment of alternative risk measures is relevant given the debate among regulators, industry representatives and academics about how adequately they are used. The author borrows the approach in parts from the work of Barth. Barth compares the ruin probability and EPD approach when discussing the RBC formulas of the US National Association of Insurance Commissioners introduced in the 1990s. The author reconsiders several of these findings and discusses them in the light of the new regulatory frameworks. More precisely, the author first performs sensitivity analyses for the risk measures using different parameter configurations. Such analyses are relevant since in practice parameter values may differ from estimates used in the model and have a significant impact on the values of the risk measures. Second, the author goes beyond a simple discussion of the outcomes for each risk measure, by deriving the firm conclusion that both the frequency and magnitude of shortfalls need to be controlled.

This paper considers a Sparre Andersen risk process for which the claims inter‐arrival distribution is Generalized Exponential. The purpose of this paper is to find explicit expressions for the moments of time to ruin when a penalty is imposed at ruin.

The study is focused on the function ϕ_δ(u), the expected discounted penalty, which is due at ruin and may depend on the deficit at the time of ruin and also on the surplus prior to ruin. It shows that ϕ_δ(u) satisfies an integro‐differential equation which is solved using Laplace transforms.

The authors have chosen a penalty function, which is independent of the surplus immediately before ruin, and a closed form expression is obtained for ϕ_δ(u), and then solved for the moments of time to ruin.

New results are derived, many of which have mathematical and probabilistic interpretations, and additional insight is gained for the results in the renewal risk model.

This chapter considers the environmental damage related to Ireland’s recent ‘ghost estates’, placing this disastrous waste of resources in the long historical context of ancient ruins that also dot the land.

It considers ruins from an ecocritical perspective, as material artefacts attesting directly to people’s relationship with their environment.

From ancient megaliths and sacred sites to imposing castles, Ireland’s impressive ruins ignite romantic reflections in many. Yet, just like the modern ruins of ghost estates, they also tell of an often oppressive relationship between human cultures and the natural environment. Ironically perhaps, stone circles and tombs that seem to speak of people living in much closer relation to non-human nature than we moderns do are also associated with the environmental scourge of deforestation. Yet, they at least stand testament to an ethic of timelessness and robust building, as well as resistance to a seemingly irresistible process of capitalistic modernisation; the recent ruins are devoid of such ethical commitments. Given this, however, creative responses should also be noted to the logic of the ghost estates, including Cloughjordan’s Ecovillage and the NamaLab project.

Three sets of responses that all work more realistically with a recognition of the limits of sustainable development are considered in the conclusion: Transition Towns, an Ecovillage and architectural reutilisation of defunct buildings.

The city of Fortaleza, capital of the state of Ceará in the north-east of Brazil, presents a paradox as a present-day tourist destination, while also marked by features and processes characteristic of cities in the Global South, such as high levels of social inequality with fragmented urban margins and vulnerabilities. This research problematizes the idea of “historical ruins” proposed by Walter Benjamin as a viable way to understand how the organization process of today's city margins can be “denaturalized” by the past. The objective of this research is to assess how the urban margins of the city were organized as a history of resistance.

In theoretical terms, this research links critical urban studies with critical approaches to organizational history (COH) based on Walter Benjamin's philosophical concepts of “ruins” and “progress”. The historical and archival methodology, consisting of 193 documents, suggests the existence of a philosophical–historical nexus that helps explain the spatial fragmentation of the city, and especially the urban margins in the western region of Fortaleza.

The Benjaminian notion of “historical ruins” has been exemplified by the Brazilian government practices confining migrants fleeing drought in internment camps on the margins of the city of Fortaleza in three waves beginning in 1877, 1915 and 1932 respectively. The effects of such confinement policies put into practice in the name of “progress” influenced the organization of large urban spaces on the city's margins, whereas on the other hand, the analyses advanced in this research reflect on alternatives to re-frame the history of the organization of the margins of Fortaleza through a set of practices of resistance.

Based on the concept of “denaturalization”, and through re-activation of the memory of a circumstantial past, the gaze of the “ruins”, as represented by the belief in “progress” addressed in official reports of government confinement policies, spaces of resistance have emerged where new possibilities for the future of the city can be imagined.

Points out that ruins have long held a fascination for those concerned with images of picturesque charm or sublime horror. Recent attitudes have broadened in an appreciation of the potential that standing ruins and their sites have for students of architecture, archaeology and landscape history, while many are now examining the roles that these remains might also have for the flora and fauna of a particular location. Examines the work that is being undertaken to consolidate and repair a number of ruined churches within the county of Norfolk. Illustrates how such work can broaden the base from which other projects may be undertaken.

The purpose of this paper is to investigate how queueing theory has been applied to derive results for a Sparre Andersen risk process for which the claim inter‐arrival distribution is hyper Erlang.

The paper exploits the duality results between the queueing theory and risk processes to derive explicit expressions for the ultimate ruin probability and moments of time to ruin in this renewal risk model.

This paper derives explicit expressions for the Laplace transforms of the idle/waiting time distribution in GI/HE_r(k_i,λ_i)/1 and its dual HE_r(k_i,λ_i)/G/1. As a consequence, an expression for the ultimate ruin probability is obtained in this model. The relationship between the time of ruin and busy period in M/G/1 queuing system is used to derive the expected time of ruin.

The study of renewal risk process is mostly concentrated on Erlang distributed inter‐claim times. But the Erlang distributions are not dense in the space of all probability distributions and therefore, the paper cannot approximate an arbitrary distribution function by an Erlang one. To overcome this difficulty, the paper uses the hyper Erlang distributions, which can be used to approximate the distribution of any non‐negative random variable.