The study proposes and tests a risk-free rate model that simultaneously lets the risk-free rate migrate between rating categories as risk-free rate ranges, and follow a random walk within rating categories as risk-free rate ranges. Although the study arbitrarily assigned rating categories, and risk-free rate ranges to the rating categories, empirical research can clarify this, by examining the relationship between the risk-free rate and risk-free rate volatility, and by examining the relationship between sovereign credit ratings and risk-free rate ranges as well as risk-free rate volatility. Firstly, comparable risk-free rates should illustrate comparable risk-free rate volatility, and risk-free rates should cluster in terms of their risk-free rate volatility characteristics. Secondly, sovereign credit ratings should demonstrate risk-free rate ranges and risk-free rate volatility characteristics. To test the model, a risk-free bond portfolio, together with a risk-free rate rating...
Category - Brian BARNARD
WITS Business School, The University of the Witwatersrand, South Africa
The study reviews equity valuation, and proposes an alternative equity valuation model based on a random process modelling of earnings and equity growth. A Markov process is used to model earnings, standardized as earnings to book value, and book value based on rating category. This assumes a distinct relationship between rating category, and standardized earnings as well as book value: that both standardized earnings as well as book value are comparable per rating category, but distinct across rating categories. It is also assumed that a company inherits the earnings and book value distribution of its current rating. To test the premises of the equity valuation model, the study examines the standardized earnings and book value distributions of rating categories. The research population comprised all publicly-traded, rated equity of the JSE and NYSE stock markets. Sample data was limited to all equity of the major rating categories (AAA, AA, A, BBB, BB, B) for the 8 year window period...
