***** To join INSNA, visit http://www.insna.org ***** Thanks to Joe and David and Kathleen for your responses. I will look into ORA and Siena as an alternative to HLM. I was hoping to hear from someone about why a multilevel model was not appropriate before taking on another analysis plan. Anyone have any thoughts on that? Roy Hi Roy, I suppose you could run a SIENA model, include both the density parameter as you would normally do, and then add a square of the density parameter to test for the inverted-U shaped relationship you're expecting. Joe Giuseppe (Joe) Labianca Gatton Endowed Associate Professor of Management Gatton College of Business & Economics LINKS Center for Social Network Analysis University of Kentucky Lexington, KY 40506 859-257-3741 (office) 404-428-4878 (mobile) http://linkscenter.org/ On Mon, Nov 14, 2011 at 1:37 PM, Money, Roy <[log in to unmask]<mailto:[log in to unmask]>> wrote: ***** To join INSNA, visit http://www.insna.org ***** I made a simiilar post to this list last month that garnered only one response so I am trying again. I have 8 waves (at 6 month intervals) of social network data for a interdisciplinary research consortium of scientists where the degree centrality measure peaks at wave 4 (18 months), and the geodesic distance bottoms out at that time point. It does seem like 18 months represents a maximum effect time for the aggregate network data. Previously I used UCINET to do bootstrapped t tests for particular pair-wise time comparisons but I want to characterize the longer trajectory and the apparent change in slope at 18 months. I also have associated survey response data for which I have used a discontinuous level-1 HLM individual growth model to test the hypothesis that the slope changes at time 4 (18 months). I would like to apply a similar analysis to the individual network measures of degree centrality and geodesic distance. However I have not found in my literature searches any references to the analysis of longitudinal social network data like I am working with. Is a multilevel or HLM analysis an appropriate method to test for quadratic or piecewise non linear change of the individual newtwork measures ? If not, what would be optimal ways to evaluate this apparent maxing out of the connectivity of the social network about mid way through the consortium history? Thanks for any suggestions or references. Roy Money Yale University _____________________________________________________________________ SOCNET is a service of INSNA, the professional association for social network researchers (http://www.insna.org). To unsubscribe, send an email message to [log in to unmask]<mailto:[log in to unmask]> containing the line UNSUBSCRIBE SOCNET in the body of the message. _____________________________________________________________________ SOCNET is a service of INSNA, the professional association for social network researchers (http://www.insna.org). To unsubscribe, send an email message to [log in to unmask] containing the line UNSUBSCRIBE SOCNET in the body of the message.