Portfolio theories guide the investors to select securities that will maximize returns and minimize risk. These theories can be classified into different categories as depicted in figure 6.1. I. Traditional Approach: 1. Dow Theory: Charles Dow, the editor of Wall Street Journal, USA, presented this theory through a series of editorials. Dow formulated a hypothesis that the stock market does [...]
William Sharpe (1964) published the Capital Asset Pricing Model (CAPM): According to CAPM, return of a portfolio is equal to the sum of risk-free rate of return and a risk premium that is proportional to its beta. As per this model, risk and return are linearly associated. Ri = Rf+ βi (Rm-Rf) Where, Ri = Risk free rate of return [...]
Systematic risk can be measured using beta. Stock Beta is the measure of the risk of an individual stock in comparison to the market as a whole. Beta is the sensitivity of a stock's returns to some market index returns (e.g., S&P 500). Basically, it measures the volatility of a stock against a broader or more general market. It is [...]