 What is inputted into the binomial sampling equation, \(p'\), when the dynamics of the system are calculated using the temporally variable selection model is never the same as what is inputted into the binomial sampling equation when the dynamics of the system are treated as solely a function of drift. In the latter case, the input into the equation is just \(p\). But since the temperature always favors one or another type, post-selection frequency, \(p'\) is never equal to pre-selection frequency, \(p\). Treating a system of warm/cold type that undergoes temporally variable selection as though it undergoes drift would lead to making false inferences about its dynamics. Cases of temporally variable selection of the warm/cold sort simply must be modeled using type recursions in which fitness parameters are a function of time; the pioneering analysis of such systems was done by Dempster (1955). The above point generalizes: what is quantifiable as selection and drift in type recursions is made definite by how fitness variables and effective population size function in those models.