Investment diversification as a strategy for reducing investment risk

Abstract

Investment diversification is a widely accepted investment strategy, aimed at reducing investment uncertainty, while simultaneously keeping the expected return on investment unaltered. The development of investment diversification coincided with the development of portfolio theory. At the time when traditional portfolio theory was recognized as the leading portfolio management practice, the simple diversification of investments was the most commonly used strategy; however, due to its inability to recognize the importance of the correlation between returns on different investments, simple diversification was later rejected in modern portfolio theory and replaced with efficient diversification. The research study is aimed at conducting a comparative analysis between the simple and efficient diversifications of investments, together with the inevitable analysis of the optimal number of securities in a portfolio and the testing of the validity of the international diversification of investments. By applying a qualitative research methodology, it is concluded that the benefits of the international diversification of investments are still substantial, and as such outweigh specific limitations, and that the number of securities in a portfolio should be increased as long as its marginal benefits, in the form of reduced investment risk, exceed its marginal costs - in terms of increased portfolio management costs, which also represents the main result of the research.