This diploma thesis deals with optimization models of financial risks. The first part, which is devoted to the theoretical background, introduces the basic concepts of optimization, modern portfolio theory, fundamental and technical analysis and statistical background. The basic principles of operation of modern portfolio theory are presented. The methods for analysis and selection of assets called Growth at A Reasonable Price and portfolio optimization approach according to Harry Markowitz were used with selected methods. The practical part is focused on the data analysis, selection of assets and design of a portfolio optimization model according to selected conditions with an emphasis on minimizing investment risk. The used models examine the selected data and are solved using the MS Excel add-in Solver version.

Leaders of nonprofits businesses adopt revenue diversification strategies to create innovative program services, creative ways to source materials, utilize volunteers and community partnerships, and identify business solutions related to solving societal problems. To continue providing services, it is crucial for nonprofit leaders to maintain adequate financial resources. The purpose of this single-case study was to explore revenue diversification strategies used by 3 leaders of a nonprofit organization in western California of the United States using Markowitz's modern portfolio theory as the conceptual lens. Data were collected through in-depth semistructured interviews and examination of organizational documents, internal archival data, and online databases. Through thematic analysis, 8 revenue diversification themes emerged: adding income streams; establishing practical financial performance measures; establishing operating reserve; achieving financial health, sustainability, and resilience; building organizational capacity; adopting transparency; achieving efficiency and effectiveness; and conducting active surveys. Additionally, 10 recommendations were identified: developing written procedurals, developing a process improvement strategy, engaging in contingency planning, increasing transparency and governance, using metrics for donor attrition and retention, developing and upgrading technology, increasing staff capacity, creating an employee handbook, conducting active surveys to reinforce additional services, establishing performance measures. These findings may have implications for positive social change, including the potential to contribute to nonprofit leaders' models of effective strategies with processes to grow income sources to support organizational sustainability and support a leader's ability to improve and maintain service offerings, while avoiding dependence on single source of revenue.