COMPARATIVE STUDY OF PORTFOLIO THEORIES
This article undertakes a comparative study of portfolio theory in different approaches in stock market investment. This study is comparing four models of portfolio theory in traditional approaches and modern approaches. We are comparing the Dow Theory, Random Walk Theory Markowitz theory and Sharpe single index model each other. This paper is investigating the bases of the criteria of nature, of theory strategy of theory investment process of theory applicability of theory of different theory’s.