Jens Rasmussen (1926-2018)

Today I discovered that early this year Jens Rasmussen had died. This is a loss for the field of human factors, cognitive engineering, and mental models.

My thesis work on function allocation at the University of Illinois was based on Jens’ Knowledge-Rules-Skills Decision Making Model. That same model contributed to the creation of the root cause – Knowledge-Based Decision Required – on the TapRooT® Root Cause Tree®. Jens helped in my early root cause analysis development work by reviewing some of my early ideas. We still teach his model in our 5-Day TapRooT® Advanced Root Cause Analysis Team Leader Course.

I had not had the opportunity to talk to Jens for many years but still truly appreciate the guidance he provided in my early human factors research and development of root cause systems.