John Eugene (Gene) Tyworth

John J. Coyle Endowed Professor Emeritus of Supply , John J. Coyle Endowed Professor of Supply Chain Management
Department: Supply Chain and Information Systems
Office: 413 Business Building
Phone: 814-865-1866
Fax: 814-863-7067
Member of Faculty Since: 1976


Since joining the Smeal College faculty in 1976, Dr. Tyworth has taught graduate and undergraduate courses in supply chain and logistics management. His work experience includes traffic management and air cargo operations. He was an active duty officer in the Air Force from 1967-71, when he performed transportation/logistics duties under the Strategic Air Command and the 14th Air Force (RVN). In addition, he continued his service from 1976-1994 as reserve officer in the acquisition/procurement area for HQ Air Force and later for DLA. He also has consulting experience with major companies in the railroad, trucking, air cargo, food products, forest products, wire and cable, offshore rig/platform supply, and information technology industries.

Current Research

Dr. Tyworth's research focuses on inventory-theoretic models for mode choice and total logistics costs.


Out-of-stock (OOS) risk
Total landed cost analysis
Inter-modal freight flow analysis

Publication List

Tyworth, J.E. and J. Saldahna (2014), "The lead-time reliability paradox and inconsistent value-of-reliability estimates", Transportation Research Part E, 70, 76-85.

JC Hayya, RV Ramasesh, JG Kim, and D Sun (2013), "JIT Delivery with Stochastic Lead Time", Journal of the Operations Research Society, 64, 97-105.

Saldahna, J., J.E. Tyworth, P. F. Swan, and D. Russell (2009), "Cutting Logistics Costs with Ocean Carrier Selection", Journal of Business Logistics, 30, 2, 175-195.

Thomas, D. and J. E. Tyworth (2007), "Is Pooling Lead-Time Risk by Splitting Orders Simultaneously Worthwhile?", Journal of Business Logistics, 28, 1, 169-193.

Thomas, D. and J. E. Tyworth (2006), "Pooling Lead-Time Risk by Order Splitting: A Critical Review", Transportation Research Part E: Logistics and Transportation Review, 42, 4, pp. 245-257.

Saldanha, J. P., D. M. Russell, and J. E. Tyworth (2006), "A Disaggregate Analysis of Ocean Carriers' Transit Time Performance", Transportation Journal, 45, 2, 39-60.

Freimer, M., D. Thomas, and J. E. Tyworth (2005), "The Value of Setup Cost Reduction and Process Improvement for Economic Production Quantity Model with Defects", European Journal of Operations Research, 173, 241-251.

Swan, P. and J. E. Tyworth (2001), "Shipper Sensitivity to Unreliable Service in Carload Markets", Transportation Journal, 40, 2, 16-25.

Suzuki, Y., J. E. Tyworth, and R. A. Novack (2001), "Airline Market Share and Customer Service Quality: A Reference Dependent Model", Transportation Research A, 35, 773-788.

Tyworth, J. E. and Alex Ruiz-Torres (2000), "Transportation's Role in Sole Versus Dual Sourcing Decision", International Journal of Physical Distribution and Logistics Management, 30, 2, 128-144.

Tyworth, J. E. and R. Ganeshan (2000), "A Note on the Solution to the Inventory Model for Gamma Lead-Time Demand", International Journal of Physical Distribution and Logistics Management, 30, 6, 534-539.

Ganeshan, R., J. E. Tyworth, and Yuanming Guo (1999), "Dual-Sourced Supply Chains: The Discount Supplier Option", Transportation Research E, 35, 1, 11-23.

Tyworth, J. E. and Amy Zhaohui Zeng (1998), "Estimating the Effects of Carrier Transit-Time Performance on Logistics Cost and Service", Transportation Research A, 32, 2, 89-97.

Suzuki, Y. and J. E. Tyworth (1998), "A Theoretical Framework for Modeling Sales-Service Relationships in the Transportation Industry", Transportation Research E, 34, 2, 87-100.

Tyworth, J. E. and Liam O'Neill (1997), "Robustness of the Normal Approximation of Lead-Time Demand in a Distribution Setting", Naval Logistics Research, 44, 165-186.

Tyworth, J. E., Y. Guo, and R. Ganeshan (1996), "Inventory Control Under Gamma Demand and Random Lead Time", Journal of Business Logistics, 17, 1, 291-304.


Supply Chain Forum (Editorial Board: 1999-present)

Transportation Journal (Editorial Board: 1985-present)

Journal of Business Logistics (Associate Editor 2010-present)


Ph.D., Logistics, Lundquist College of Business, University of Oregon, 1975

M.B.A., Logistics, Lundquist College of Business, University of Oregon, 1973

B.A., Economics, University of California Santa Barbara, 1966


SCM 421, Supply Chain Analytics

SCM 810, Transportation & Distribution Management (on-line graduate)