I knew him as a mentor back in the day. In person he went by "Stewart Bainbridge". Which also answers the question asked by @a3nm about what the "S" stands for. I never heard about the "Edwin" so presumably it was a given name he wasn't fond of.
Based on a quick search through the University of Michigan library catalog, I'm pretty sure it's "Edwin"; see, for example, this technical report "A Class of Sequential Sampling Problems Arising in Certain Learning Situations" (1967).