This was just posted to the multilevel listserv, and I have taken a very quick glance. It appears to offer an alternative form for estimating degrees of freedom. It's focused on longitudinal data, and I have not looked closely enough to see whether it would be more generally applicable to mixed-models (multilevel, nested, crossed, etc.) or whether it would "scale up" for larger problems. Given all the hoo-hah around dfs, thought I would at least kick it out to the group. cheers, Dave -------- Original Message -------- Subject: effective sample size Date: Tue, 17 Nov 2009 09:12:47 -0600 From: Stas Kolenikov <skolenik at GMAIL.COM> Reply-To: Multilevel modelling discussion list <MULTILEVEL at JISCMAIL.AC.UK> To: MULTILEVEL at JISCMAIL.AC.UK The recent issue of The American Statistician contains a pretty neat paper on the effective sample size and degrees of freedom in longitudinal studies: see http://www.citeulike.org/user/ctacmo/article/6129798. Highly recommended; there aren't that many people who understand longitudinal data as well as the Geert duo. -- Stas Kolenikov, also found at http://stas.kolenikov.name Small print: I use this email account for mailing lists only. -------------------------- Multilevel list -------------------------- To leave, send leave multilevel to jiscmail at jiscmail.ac.uk For further info about the Multilevel list, please see http://www.jiscmail.ac.uk/lists/multilevel.html and http://www.nursing.teaching.man.ac.uk/staff/mcampbell/multilevel.html
Dave Atkins, PhD Research Associate Professor Center for the Study of Health and Risk Behaviors Department of Psychiatry and Behavioral Science University of Washington 1100 NE 45th Street, Suite 300 Seattle, WA 98105 206-616-3879 datkins at u.washington.edu