The Estimable Functions of Age, Period and Generation Effects: A Political Application

In traditional social research, it is customary to assume that the birth cohort, period and age are scaled as follows: cohort = period – age. Starting from this constraint, the joint analysis of the three effects is not estimable, as one phenomenon is completely determined by the remaining two. In this study we will see how, in given situations, the use of the concept of political generation, to replace the cohort concept normally used, allows us to overcome this obstacle and how in this case estimable models may easily be created.