Diversification of equity investment portfolios. Application to the IBEX 35

At present, there is no unanimity on the effects that stock diversification can have on the total risk of an investment portfolio. In this context, this paper studies some issues related to the evolution of risk in an investment portfolio made up of IBEX 35 stocks. In addition, it is tested whether conclusions drawn for other time periods and in other markets are applicable to the Spanish stock market. The methodology used consists of calculating how the two components that make up the total risk of a portfolio (systematic risk and unsystematic risk) behave as portfolios of increasing size are diversified. The study shows how an increase in the number of securities in the investment portfolio decreases the percentage corresponding to the unsystematic risk component and increases the systematic risk component. Furthermore, it also shows that the benefits of diversification become increasingly marginal as portfolio size increases. Additionally, it is shown that an increase in the number of securities also increases the stability of the Beta of the investment portfolios over time.

THE IMPACTS OF INDIVIDUAL INFORMATION ON LOSS RESERVING

The projection of outstanding liabilities caused by incurred losses or claims has played a fundamental role in general insurance operations. Loss reserving methods based on individual losses generally perform better than those based on aggregate losses. This study uses a parametric individual information model taking not only individual losses but also individual information such as age, gender, and so on from policies themselves into account. Based on this model, this study proposes a computation procedure for the projection of the outstanding liabilities, discusses the estimation and statistical properties of the unknown parameters, and explores the asymptotic behaviors of the resulting loss reserving as the portfolio size approaching infinity. Most importantly, this study demonstrates the benefits of individual information on loss reserving. Remarkably, the accuracy gained from individual information is much greater than that from considering individual losses. Therefore, it is highly recommended to use individual information in loss reserving in general insurance.

On the Relationship between Investment Risk and Insurance Solvency Optimum

Solvency is a key issue in the insurance sector. Investments can have significant risks, and a compelling research question is whether the solvency optimizing investment risk corresponds to the lowest possible risk level. This question is even more topical with some interest rates approaching very low levels in many countries. The paper aims to answer this question. Theoretical results suggest that if insurance risk and investment risk are uncorrelated, solvency optimizing investment portfolios with non-risk-free components may exist, and the level of optimal investment risk may inversely depend on the insurance portfolio size.

For-Profit Hospitals Out of Business? Financial Sustainability During the COVID-19 Epidemic Emergency Response

This perspective argues that for-profit hospitals will be heavily affected by epidemic crises, including the current coronavirus disease 2019 (COVID-19) outbreak. Policy-makers should be aware that for-profit hospitals in particular are likely to face financial distress. The suspension of all non-urgent elective surgery and the relegation of market-based mechanisms that determines the allocation and compensation of care puts the financial state of these hospitals at serious risk. We identify three organisational factors that determine which hospitals might be most affected (ie, care-portfolio, size and whether it is private equity [PE]-owned). In addition, we analyse contextual factors that could explain the impact of financial distress among for-profit hospitals on the wider healthcare system.