In parallel with the popularization and widespread diffusion of the internet, interest in the concept of different business models (BM) has increased dramatically, attracting the attention of both scholars and managers alike (Dodgson, Gann and Phillips, 2013). As a result, an increasing number of businesses decide to establish themselves and compete in the digital arena (Lee, 2001); many of which are employing what is called a platform model capitalizing on the ability to operate with several BMs simultaneously (Gu, Kannan and Ma, 2018; Aversa, Haefliger, Hueller and Reza, 2021). The purpose of this study is to explore how a digital platform company can manage a diversified business model portfolio in a digital platform context. Theoretical concepts relevant to the subject were used to analyze the challenges and opportunities of operating with a diversified BM portfolio, as illustrated in our two research questions: 1) What are the challenges and opportunities in operating with a diversified BM portfolio? and 2) How could a new model be integrated into a diversified BM portfolio with B2C, B2B and B2B2C models already employed? A single case study approach was used in this study in the form of in-depth interviews with executives at a company with a diversified business model portfolio, coupled with data from annual reports and strategic documents to strengthen the empirical foundation. Even though the most commonly voiced drawbacks with a case study design often revolves around the generalizability (or lack thereof), we believe that the findings presented in this study are sufficiently generalizable and broadly applicable, especially considering the prevalence of contextually similar companies (digital companies with a platform model and diversified BM portfolios). The empirical findings highlighted several vital aspects of successfully managing a diversified BM portfolio; the importance of resource management as well as the value of creating a long-term strategy. In short, this study showed that a diversified BM portfolio can provide a) increased firm capacity utilization through effective resource allocation, b) a safeguard toward market fluctuations via multiple revenue streams, c) leverage of resources through BM exploitation and exploration and d) a source of competitive advantage as a result of the complexity of the system. However, the aforementioned benefits are not devoid of challenges. Most notably how to prevent undermining parts of the core business as a result of cannibalization, which could be managed using a Phased Integration Strategy.

This thesis introduces various approaches to natural catastrophe risk assessment in (re)insurance environment. Most emphasis and further elaboration is put on probabilistic models in comparison to the standard model as proposed by Solvency II. The outcomes of natural catastrophe modeling play an important role in the design of proper actuarial models related to catastrophe risk. More specifically it is shown that they can be entirely understood in a wider actuarial context, namely risk theory. Within the Solvency II framework, probabilistic model outcomes are translated by means of the proposed decomposition methodology putting them into a similar language of the standard formula in order to create the ability to compare different results implied by either probabilistic model or standard formula. This enables both comparison of the implied dependence structure of probabilistic model to standardized correlations assumed in Solvency II, and scenario year loss factors of Solvency II to implied damage factors of probabilistic models in defined cresta zones. The introduced decomposition methodology is illustrated by flood and windstorm model outcomes calculated on exposure data of Czech insurance companies and compared to the respective standard formula parameters and outcomes. Finally, other applications of the proposed decomposition methodology are introduced, such as measurement of diversification effect or blending of different results calculated by different models or even approaches to natural catastrophe risk assessment.