Observations on the Duration of Ph.D. Programs
Herbert C. Ratz · IEEE Transactions on Systems Man and Cybernetics · 1975
A statistical distribution is reported for the lengths of Ph.D. programs from which are derived functions analogous to those of elementary reliability theory. These show that the anticipated future duration of these research programs does not decrease uniformly, so that there are diminishing returns from further work almost to the point where the expected date of completion remains a constant distance in the future.