title: The R code for computing the Cohen's f2 effect size (for multilevel models)
body: <p>Until now, I have not found the R syntax for computing the f² Cohen's effect size. There's this <a href="http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3328081/" rel="nofollow">paper</a> from Selya et al. (2012) that talks about it and that gives the SAS code. There's also the Stata code <a href="http://www.ats.ucla.edu/stat/stata/faq/xtmixed_effect_size.htm" rel="nofollow">here</a>. If I dare to ask, can anyone here transpose the SAS or Stata code into R code ? I will REALLY appreciate the help if my wish is granted.</p>