Effect sizes for mixed-effects models
we want to derive the variance related to Cohen?s d for a mixed-subjects design with some participant conducting a task only in the control condition and other participants conducting the task in the control and in the experimental condition (within-subjects design).
[...] we only have access to parts of the raw data-sets
Do you have the raw data or appropriate summary statistics from this mixed-subjects study? Could you get it? I think the "usual" approach would be to use a conservative lower bound for the effective sample size. Cheers, David Duffy.