Method of Incorporating Risk
Theory - For the present, let us accept variance as a measure of risk. How does current theory incorporate risk into investment analysis such that, given two investments with different returns and different risks, the factors can be adjusted to reach a single figure with which to compare the investments? Two adjusted discount rate approach. When the method of certainty equivalent is used, the value of an investment is calculated by discounting the random cash flows at the pure rate of interest. The resulting expected value and variance are converted into their certainty equivalent with the risk eliminated. This certainty equivalent figure determines the profitability of the investment. Under the method of risk-adjusted discount rate, the value of an investment is calculated by discounting the expected cash flow at a rate that allows for the time value of money and also for the risk present in the cash flow. The investment is profitable if the resulting value is positive.