what is the definition of diversity variable in sas what is r comp variable what is the role of the isref in an experiment? what is isref what is isref a gmo variable? what is the difference between comp and ref what is the purpose of sas comp which of the following is a type of random variable sas comp random variable is isref considered a class variable how to model the random variable gmo in r what is the purpose of isref in r what is the purpose of sas comp model what is isref what is random variable sas what is the purpose of sas what is the difference between comp and isref in sas what is a variety variable in r what is the purpose of r for generating a variable in sas lmer what is r variable isref