The capital asset pricing model (CAPM) provides one method of determining a discount rate in business valuation. The CAPM originated from the Nobel Prize-winning studies of Harry Markowitz, James Tobin, and William Sharpe. The method derives the discount rate by adding risk premium to the risk-free rate. The risk premium is derived by multiplying the equity risk premium with "beta", a measure of stock price volatility. Beta is compiled by various researchers for particular industries and companies, and measures systematic risks of investment.