[scott_s]

I guarantee that UPS has had teams of computer scientists, mathematicians and probably statisticians working on package scheduling and routing over the decades. The traveling salesman problem, which UPS package routing is, is an NP-hard problem, which means that guaranteeing an optimal solution is going to take an exponential amount of time. There is no "established" way to exactly solve NP-hard problems with large inputs in a reasonable amount of time. Rather, there are approximate approaches which use domain-specific information to inform what kind of heuristics one can use to achieve a tolerable result.

[mswen]

Totally agree with you. Oddly enough I am currently doing a market research project on commercial applications for Quadratic Unconstrained Binary Optimization (QUBO) and also Constrained Binary Optimization. Anyway we were talking about UPS, and just for reference if I search my 3 degree network on LinkedIn for the combination of CPLEX (an IBM optimization package) and UPS I got almost 400 hits. Now admittedly some of those people used to work at UPS, some work there now. But there are clearly many, many computer scientists, operations research scientists and mathematicians working on these and other optimization problems at UPS.

On the other hand the grandparent comment just illustrates how even with all those optimization resources individual "decisions" may still be stupid in the moment even though the overall solution is "good enough".

[freehunter]

Yeah, UPS is pretty famous for how much effort they put into optimizing routes: https://www.ups.com/us/en/services/knowledge-center/article....

I highly doubt someone could beat them in an hour at a hackathon by just saying “shortest path first” and calling it solved.