Herman Rubin was Principal Advisor to Herbert Solomon, the very first PhD candidate to receive his degree from Stanford University’s Department of Statistics, in 1950. After departing Stanford, he joined the University of Oregon and then Michigan State University, winding up at Purdue University in West Lafayette, Indiana, where he remained as Professor of Statistics and Mathematics. Professor Rubin passed away on April 23, 2018, at the age of 91. His colleagues at Purdue have planned a memorial symposium to celebrate his life and legacy on June 8th.
The following vignette is part of Herman's personal web site, where he no doubt hoped these insights would reach as wide an audience as possible!
I am often requested to repost my five commandments. These are posted here without exegesis.
For the client:
1. Thou shalt know that thou must make assumptions.
2. Thou shalt not believe thy assumptions.
For the consultant:
3. Thou shalt not make thy client's assumptions for him.
4. Thou shalt inform thy client of the consequences of his assumptions.
For the person who is both (e. g., a biostatistician or psychometrician):
5. Thou shalt keep thy roles distinct, lest thou violate some of the other commandments.
The consultant is obligated to point out how their assumptions affect their views of their domain; this is in the 4th commandment. But the consultant should be very careful in the assumption-making process not to intrude beyond possibly pointing out that certain assumptions make large differences, while others do not. A good example here is regression analysis, where often normality has little effect, but the linearity of the model is of great importance. Thus, it is very important for the client to have to justify transformations. There are, unfortunately, many fields in which much of the activity consists of using statistical procedures without regard for any assumptions.