Imagine you're a researcher studying how sleep affects mood. To explore the connection, you would look at two key "variables": sleep (how much someone gets) and mood (how happy or irritable they feel) ...

Florida Scientist, Vol. 70, No. 2 (Spring, 2007), pp. 157-165 (9 pages) The study tested the effects of controlled variables on decomposition of buried bodies in Florida. Twenty-four domestic pig (Sus ...