A First Look at the Accuracy of the CRSP Mutual Fund Database and a Comparison of the CRSP and Morningstar Mutual Fund Databases
This paper examines problems in the CRSP Survivor Bias Free U.S. Mutual Fund Database (CRSP, 1998) and compares returns contained in it to those in Morningstar. The CRSP database has an omission bias that has the same effects as survivorship bias. Although all mutual funds are listed in CRSP, return data is missing for many and the characteristics of these funds differ from the populations.(...)