Rick Froman wrote, "............. if your outcome is a physical measure of health, you can see if those pet-lovers exposed to pets have better health outcomes than those not exposed to pets."
Rick makes a point that we need to impress on all our students, i.e., the importance of interactions. We get so caught up in looking for "main effects" (e.g., pets are good for our health) that we too often fail to look for the obvious interactions, (e.g., pets are good for the health of those who love pets but not necessarily for the health of non-pet lovers). My old mentor used t say that "there's no such thing as a main effect." It's a great point. Even something such as the effect of oxygen being necessary for life depends on the organism in question.. or the universe in which the effect if being observed. So a "main effect" is really just a useful fiction. Ed Edward I. Pollak, Ph.D. Department of Psychology West Chester University of Pennsylvania http://home.comcast.net/~epollak/home.htm ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Husband, father, grandfather, biopsychologist, & bluegrass fiddler...... in approximate order of importance. --- You are currently subscribed to tips as: [email protected]. To unsubscribe click here: http://fsulist.frostburg.edu/u?id=13090.68da6e6e5325aa33287ff385b70df5d5&n=T&l=tips&o=7741 or send a blank email to leave-7741-13090.68da6e6e5325aa33287ff385b70df...@fsulist.frostburg.edu
