Joined the faculty at the University of Houston in the fall of 1985. He received his doctorate in Statistics from Oklahoma State University and has articles published in journals such as Annals of Statistics, Communications in Statistics, Journal of Statistical Planning and Inference, International Journal of Forecasting, and Estadistica. Dr. Diaz-Saiz has served as a referee for numerous scientific journals and was associate editor of Communications in Statistics. Dr. Diaz-Saiz has participated in projects for a wide variety of firms in the public and private sectors in the areas of sampling design and analysis, forecasting, and inventory control. His research interests include the areas of Bayesian forecasting, inventory control, and time series analysis. His teaching interests include Bayesian statistics, time series analysis, and linear statistical models.
- Bayesian Forecasting
- Inventory Control
- Time Series Analysis
- Diaz-Saiz, Joaquin and Everette S. Gardner Jr. "Exponential Smoothing in the Telecommunications Data." International Journal of Forecasting. 
- Khumawala, Basheer, Joaquin Diaz-Saenz and John Visich. "An Empirical Comparison of Improvement Heuristics for the Mixed-Model, U-Line Balancing Problem." International Journal of Manufacturing Technology & Management.