RT Journal Article SR Electronic T1 Estimates of Smallstock Betas Are Much Too Low JF The Journal of Portfolio Management FD Institutional Investor Journals SP 104 OP 111 DO 10.3905/jpm.1997.409621 VO 23 IS 4 A1 Roger G. Ibbotson A1 Paul D. Kaplan A1 James D. Peterson YR 1997 UL https://pm-research.com/content/23/4/104.abstract AB