“Relative Importance of Risk Sources in Insurance Systems”, Edward W. Frees,April 1998

Abstract

This paper considers a Sparre Andersen collective risk model in which the distribution of the interclaim time is that of a sum of n independent exponential random variables; thus, the Erlang(n) model is a special case. The analysis is focused on the function φ(u), the expected discounted penalty at ruin, with u being the initial surplus. The penalty may depend on the deficit at ruin and possibly also on the surplus immediately before ruin. It is shown that the function φ(u) satisfies a certain integro-differential equation and that this equation can be solved in terms of Laplace transforms, extending a result found in Lin (2003). As a consequence, a closed-form expression is obtained for the discounted joint probability density of the deficit at ruin and the surplus just before ruin, if the initial surplus is zero. For this formula and other results, the roots of Lundberg’s fundamental equation in the right half of the complex plane play a central role. Also, it is shown that φ(u) satisfies Li’s (2003) renewal equation. Under the assumption that the penalty depends only on the deficit at ruin and that the individual claim amount density is a combination of exponential densities, a closed-form expression for φ(u) is derived. In this context, known results of the Cauchy matrix are useful. Surprisingly, certain results are best expressed in terms of divided differences, a topic deleted from the actuarial examinations at the end of last century.     

Analytic derivatives and the computation of GARCH estimates

In the context of univariate GARCH models we show how analytic first and second derivatives of the log-likelihood can be successfully employed for estimation purposes. Maximum likelihood GARCH estimation usually relies on the numerical approximation to the log-likelihood derivatives, on the grounds that an exact analytic differentiation is much too burdensome. We argue that this is not the case and that the computational benefit of using the analytic derivatives (first and second) may be substantial. Furthermore, we make a comparison of various gradient algorithms that are used for the maximization of the GARCH Gaussian likelihood. We suggest the implementation of a globally efficient computation algorithm that is obtained by suitably combining the use of the estimated information matrix with that of the exact Hessian during the maximization process. As this would appear a straightforward extension, we then study the finite sample performance of the exact Hessian and its approximations (that is, the estimated information, outer products and misspecification robust matrices) in inference.     

The problem of employees' network centrality and supervisors' error in performance appraisal: A multilevel theory

This article reveals an unexplored paradox for HR managers: the centrality of an employee in the social network benefits performance but hampers performance appraisal because it affects supervisors' rating errors. Central employees can be erroneously rated high on performance even when they are not high performers because supervisors tend to overappraise their performance. A distinction is made between rating precision, which depends on supervisors' uncertainty regarding employees' performance, and rating accuracy, which depends on supervisors' bias in favor of employees. Employee centrality is posited to be beneficial to precision but deleterious to accuracy because it regulates the diffusion of positive information, status, and power, all of which distort supervisors' capacity and motivation to accurately appraise performance. It is then argued that rating errors caused by network centrality affect aggregate perceptions of justice in organizations. When employees are highly connected to each other in a dense network, organizations have a strong and positive justice climate. Yet when some employees are more central than others in a centralized network, organizations have a negative and weak justice climate. The article contributes to the literature because it identifies an unexplored dark side of network centrality and offers recommendations for HR managers to cope with its deleterious consequences and for scholars to study them.     

Applying the counseling-learning approach to a tourism-related massive open online course

ABSTRACT

This study discusses how to apply counseling-learning (CL) principles to a particular e-learning solution for teaching a tourism-related subject via a massive open online course (MOOC). Several effective caring patterns in achieving learning-related goals and being part of a community according to the CL principles are presented and discussed using the MOOC “eTourism: Communication Perspectives” as a case study. The study underlines how the MOOC platform can act as a place for contents enjoinment and active learning. Moreover, the active role of social media for increasing the engagement of learners in the proposed activities and for developing a sense of the community is identified. In particular, Facebook and Twitter can act as places for community building and informal social interactions among learners that last beyond the completion of the course, which in turn can be a valid aid for continuing the relationships among instructors/learners and learners/learners, and for reaching new ones.     

MOOCs in tourism and hospitality: a review

ABSTRACT

Massive Open Online Courses (MOOCs) have grown significantly and globally in less than ten years. However, practices and research in tourism and hospitality MOOCs remain nascent. This study proposes the MOOC Components Framework with six groups of course components: scaffolding, lectures, networking, collaboration, assessment, and affirmation. Drawing on this framework and a case study method, the study analyses 18 tourism and hospitality MOOCs from higher education institutions. The results highlight that: tourism and hospitality MOOC offerings lack diversity; the forum is the preferred communication tool; social media are comparatively underused; the discontinuity of MOOC instructors needs attention; and finally, littless multilingual support is available.     

Organizing for continuous technology acquisition: the role of R&D geographic dispersion

External technology acquisition has been proved to be an important strategy to enhance firms’ innovation performance. However, previous studies claim that companies acquiring technologies tend to not carry on with this strategy over time, thus limiting their attitude toward continuous technology acquisition. Moreover, the extant literature also highlights that this attitude is strongly influenced by their organizational structure. Therefore, in the present paper, we investigate the relationship between how firms organize R&D activities and continuous technology acquisition. Specifically, given the increasing globalization of technological development, we focus on the role of R&D geographic dispersion, and how its influence is moderated by firms’ technological diversification. We tested our hypotheses on longitudinal data of 303 biotechnology firms that acquired, at least, one USPTO patented technology over the period 1982–2012. Results reveal that R&D geographic dispersion is curvilinearly (inverted U-shaped) related to continuous technology acquisition, with negative returns occurring earlier in technology-diversified companies.     

Convergence in OECD countries: technical change,efficiency and productivity

The aim of this study is to analyse labour productivity convergence in the OECD countries over the period 1975-90. A nonparametric frontier approach is used to calculate the Malmquist productivity index. By breaking it down, the contribution in the growth of labour productivity of technical progress, of changes in efficiency, and of the accumulation of inputs per worker are quantified. Unlike other studies, the results obtained show that technical change has worked against labour productivity convergence, since it has always been greater in the countries with higher labour productivity.     

Fiscal policy effects, convergence, and growth

The objective of this paper is to create an economic growth model with public capital that determines when exogenous or endogenous growth appears, showing the optimal public sector dimension, and determines the convergence equation condition. An empirical analysis is also developed for several countries.     

Kriging methodology for regional economic analysis: Estimating the housing price in Albacete

Because of the socioeconomic importance of the housing subsector in the local, regional, and national economy and its implications for housing policy, this paper attempts to analyze the spatial behavior of the free housing price in the city of Albacete. To achieve this aim, the authors have used the models and estimators imported from geology called kriging. To do this, it is necessary to know the spatial dependence structure of the process, which is shown in the variogram.