Expected real interest rates are calculated based on nominal yields and inflation expectations from analyst surveys (consumer price inflation according to forecasts by Consensus Economics Incorporated).
The famous Fisher equation captures the relationship between nominal interest rate, expected real interest rate and investors' expectation on inflation:
Expected real interest rate = Nominal interest rate - Expected inflation rate
For example, assume a bond pays an interest rate of 5% per year. If the inflation rate is expected to be 3% next year, then the expected real interest rate on your savings is 2%.