Apologies for my delayed reply!  I replied to the email, but I don't think you received it?  My email is below: Steve, Excellent!!  You have made my day!  I can actually do you one better and provide the papers which give the complete formulations (and their derivations).  The Nakagawa and Schielzeth paper is attached as well as the update by Johnson which applies to random slopes as well as random intercept models.  Both papers also provide R code (which I have also attached) if that helps as well.  My ultimate goal is to calculate the variation explained by the some of the fixed effects in my model, and the r2 is the first step. Thank you!!! Alison P.S. I couldn't attach any files so here are the weblinks:  Johnson 2014:  http://onlinelibrary.wiley.com/doi/10.1111/2041-210X.12225/epdf Johnson 2014 R code:  http://onlinelibrary.wiley.com/store/10.1111/2041-210X.12225/asset/supinfo/mee312225-sup-0001-RScript.R?v=1&s=09ff71cf1ff0058eed83fc3c8bd694c649764767 Nakagawa & Schielzeth 2013:  http://onlinelibrary.wiley.com/doi/10.1111/j.2041-210x.2012.00261.x/epdf Nakagawa & Schielzeth 2013 R code:  http://onlinelibrary.wiley.com/store/10.1111/j.2041-210x.2012.00261.x/asset/supinfo/mee3261-sup-0004-DataS4.R?v=1&s=df4e356429d67469bbf0b0ef3125381c308df654 ... View more