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Estimating stochastic ray production frontiers
Tsionas, Efthymios G., (2019)
New insights into the stochastic ray production frontier
Henningsen, Arne, (2017)
A ray-based input distance function to model zero-valued output quantities : derivation and an empirical application
Price, Juan José, (2022)
Expense preference behavior in public transit systems
Obeng, Kofi, (2000)
Airline daily fare differentiation in a medium-size travel market
Obeng, Kofi, (2008)
The sources of output change in urban bus transit systems
Obeng, Kofi, (1990)