Cliff is a Distinguished Professor of Statistics and Texas A&M University. Cliff received his PhD under the direction of Jerry Sacks in 1976 from Northwestern. He also had the privilege of working summers for Donald T. Campbell and Bob Boruch, two very distinguished social scientists. He spent 9 years on the staff of NBS (now called NIST.) He is a founding co-editor of Chemometrics and Intelligent Laboratory. In 2006 Chemometrics and Intelligent Laboratory Systems was the worlds top interface science and mathematics journal out of 65. Since then there have been a large number of computer science math interface journals but it still is 12th out of 99 such journals and is 8th out of 122 statistics and probability journals Cliff is now editor emeritus for that journal. Cliff has coauthored a leading textbook for transportation engineers Transportation Statistics and Microsimulation, and is a senior research scientist at the Texas A&M Transportation Institute.
Cliff is lead chair of the 2015-2016 SAMSI program in forensic science and was a member of the NRC bullet lead committee. He has spoken at many scientific meetings including the AAAS annual meeting and the Joint Statistical Meetings and has frequently appeared on television, radio, and newspaper. He was a former forensic columnist for the Austin American Statesman. Cliff has served many times as an expert witness for statistical aspects of forensic science and is a member of the Houston Forensic Science Center technical advisory group (TAG).